Diagnostic yield and safety of jumbo biopsy forceps in patients with subepithelial lesions of the upper and lower GI tract.

PubMed

Buscaglia, Jonathan M; Nagula, Satish; Jayaraman, Vijay; Robbins, David H; Vadada, Deepak; Gross, Seth A; DiMaio, Christopher J; Pais, Shireen; Patel, Kal; Sejpal, Divyesh V; Kim, Michelle K

2012-06-01

EUS-FNA often fails to make a definitive diagnosis in the evaluation of subepithelial lesions. The addition of jumbo biopsy forceps has the potential to improve diagnostic yield, but published series are limited. To assess the likelihood of definitive diagnosis for subepithelial lesions by using jumbo biopsy forceps during EUS examination. Pooled retrospective analysis. 6 tertiary referral centers. All patients having undergone EUS examination for a subepithelial lesion in which jumbo biopsy forceps were used for tissue acquisition. Diagnostic yield of jumbo biopsy forceps use, complication rates, and comparison of diagnostic yield with that of EUS-FNA. A total of 129 patients underwent EUS with jumbo biopsy forceps; 31 patients (24%) had simultaneous EUS-FNA. The lesion locations were stomach (n = 98), esophagus (n = 14), duodenum (n = 11), colon (n = 5), and jejunum (n = 1). The average lesion size was 14.9 mm ± 9.3 mm. Overall, definitive diagnosis was obtained in 87 of 129 patients (67.4%) by using either method. A definitive diagnosis was provided by jumbo biopsy forceps use in 76 of 129 patients (58.9%) and by FNA in 14 of 31 patients (45.1%) (P = .175). The results in third-layer lesions were definitive with jumbo biopsy forceps in 56 of 86 lesions (65.1%) and with FNA in 6 of 16 lesions (37.5%) (P = .047). For fourth-layer lesions, the results with jumbo biopsy forceps were definitive in 10 of 25 (40.0%) and with FNA in 8 of 14 (57.1%) (P = .330). Forty-five of 129 patients (34.9%) experienced significant bleeding after biopsy with jumbo forceps and required some form of endoscopic hemostasis. Retrospective study. Jumbo forceps are a useful tool for the definitive diagnosis of subepithelial lesions. The greatest benefit appears to be with third-layer (submucosal) lesions. The risk of bleeding is significant. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

CT fluoroscopy-guided renal tumour cutting needle biopsy: retrospective evaluation of diagnostic yield, safety, and risk factors for diagnostic failure.

PubMed

Iguchi, Toshihiro; Hiraki, Takao; Matsui, Yusuke; Fujiwara, Hiroyasu; Sakurai, Jun; Masaoka, Yoshihisa; Gobara, Hideo; Kanazawa, Susumu

2018-01-01

To evaluate retrospectively the diagnostic yield, safety, and risk factors for diagnostic failure of computed tomography (CT) fluoroscopy-guided renal tumour biopsy. Biopsies were performed for 208 tumours (mean diameter 2.3 cm; median diameter 2.1 cm; range 0.9-8.5 cm) in 199 patients. One hundred and ninety-nine tumours were ≤4 cm. All 208 initial procedures were divided into diagnostic success and failure groups. Multiple variables related to the patients, lesions, and procedures were assessed to determine the risk factors for diagnostic failure. After performing 208 initial and nine repeat biopsies, 180 malignancies and 15 benign tumours were pathologically diagnosed, whereas 13 were not diagnosed. In 117 procedures, 118 Grade I and one Grade IIIa adverse events (AEs) occurred. Neither Grade ≥IIIb AEs nor tumour seeding were observed within a median follow-up period of 13.7 months. Logistic regression analysis revealed only small tumour size (≤1.5 cm; odds ratio 3.750; 95% confidence interval 1.362-10.326; P = 0.011) to be a significant risk factor for diagnostic failure. CT fluoroscopy-guided renal tumour biopsy is a safe procedure with a high diagnostic yield. A small tumour size (≤1.5 cm) is a significant risk factor for diagnostic failure. • CT fluoroscopy-guided renal tumour biopsy has a high diagnostic yield. • CT fluoroscopy-guided renal tumour biopsy is safe. • Small tumour size (≤1.5 cm) is a risk factor for diagnostic failure.

Yield of Routine Image-Guided Biopsy of Renal Mass Thermal Ablation Zones: 11-Year Experience.

PubMed

Wasnik, Ashish P; Higgins, Ellen J; Fox, Giovanna A; Caoili, Elaine M; Davenport, Matthew S

2018-06-19

To determine the yield of routine image-guided core biopsy of renal cell carcinoma (RCC) thermal ablation zones. Institutional review board approval was obtained for this Health Insurance Portability and Accountability Act-compliant quality improvement effort. Routine core biopsy of RCC ablation zones was performed 2 months postablation from July 2003 to December 2014. Routine nicotinamide adenine dinucleotide staining was performed by specialized genitourinary pathologists to assess cell viability. The original purpose of performing routine postablation biopsy was to verify, in addition to imaging, whether the mass was completely treated. Imaging was stratified as negative, indeterminate, or positive for viable malignancy. Histology was stratified as negative, indeterminate, positive, or nondiagnostic for viable malignancy. Histology results were compared to prebiopsy imaging findings. Routine ablation zone biopsy was performed after 50% (146/292) of index ablations (24 cryoablations, 122 radiofrequency ablations), and postablation imaging was performed more often with multiphasic computed tomography than magnetic resonance imaging (100 vs 46, p < 0.0001). When imaging was negative (n = 117), biopsy added no additional information (92% [n = 108] negative, 0.9% [n = 1] indeterminate, 7% [n = 8] nondiagnostic). When imaging was indeterminate (n = 19), 11% (n = 2) of biopsies had viable RCC and 89% (n = 17) were negative. When imaging was positive, biopsy detected viable neoplasm in only 10% (1/10) of cases; 80% (8/10) were negative and 10% (1/10) were nondiagnostic. Routine biopsy of renal ablation zones to validate postablation imaging results was not value-added and therefore was discontinued at the study institution. Copyright © 2018. Published by Elsevier Inc.

Do the number and volume of surgical lung biopsies influence the diagnostic yield in interstitial lung disease? A propensity score analysis.

PubMed

Fibla, Juan J; Brunelli, Alessandro; Allen, Mark S; Wigle, Dennis; Shen, Robert; Nichols, Francis; Deschamps, Claude; Cassivi, Stephen D

2015-02-01

Our objective was to evaluate whether the number and volume of surgical lung biopsies (SLB) influence the diagnosis of diffuse interstitial lung disease (ILD). Retrospective study of SLB for suspected ILD in patients from the Mayo Clinic from January 2002 to January 2010. Data were collected in the institution and analyzed. 311 patients were studied. Mean number of biopsies was 2.05 (SD 0.6); 1 biopsy in 50 (16%), 2 in 198 (63.7%), 3 in 59 (19%) and 4 in 4 (1.3%). Histopathologic diagnosis was: definitive (specific): 232 (74.6%), descriptive (non-specific): 76 (24.4%), no diagnosis: 3 (1%). After excluding patients without diagnosis (n=3), there were 50 patients with only 1 biopsy, 196 with 2 and 62 with 3 or 4; the definitive diagnostic yield was similar in all 3 groups (37/50; 74%, 150/196; 77%, and 45/62; 73%) (Chi-square, p value 0.8). The propensity score analysis between patients with 1 SLB and patients with more than 1 SLB also showed no difference in diagnostic yield. Regarding the volume of biopsies, mean total volume was 34.4 cm(3) (SD 46): 41.2 cm(3) (3 cases) in patients with no diagnosis; 33.6 cm(3) (232 cases, SD 47) in patients with specific diagnosis; and 36.6 cm(3) (76 cases, SD 44) in patients with descriptive diagnosis. Biopsy volume had no influence on histopathology yield (ANOVA, p value .8). The number and volume of the biopsy specimens in SLB did not seem to influence diagnosis. Based on our results, we believe a single sample from a representative area may be sufficient for diagnosis. Randomized prospective trials should be performed to optimize SLB for ILD. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

Saddle clamp assembly

NASA Technical Reports Server (NTRS)

Belrose, Charles R. (Inventor)

1994-01-01

A saddle clamp assembly is presented. The assembly is comprised of a hollow cylindrical body centered about a longitudinal axis and being diametrically split into semicircular top and bottom sections. Each section has a pair of connection flanges, at opposite ends, that project radially outward. A pair of bolts are retained on the top section flanges and are threadable into nuts retained on the bottom section flanges. A base member is anchored to a central underside portion of the bottom clamp body section and has a pair of connection tabs positioned beneath the bottom clamp body section connection flanges on opposite sides of the clamp axis. A pair of bolts are retained on the base member connection tabs and are threadable into a pair of nuts retainable on a support structure. The connection tab and connection flanges on each side of the clamp body are axially offset in a manner permitting downward installation/removable tool access to the lower bolts past the connection flanges. An elongated retention tether is used to connect the top clamp body section to the balance of the clamp assembly. This prevents loss of the top clamp body section when it is removed from the bottom clamp body section.

Photovoltaic panel clamp

DOEpatents

Mittan, Margaret Birmingham [Oakland, CA; Miros, Robert H. J. [Fairfax, CA; Brown, Malcolm P [San Francisco, CA; Stancel, Robert [Loss Altos Hills, CA

2012-06-05

A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

Photovoltaic panel clamp

DOEpatents

Brown, Malcolm P.; Mittan, Margaret Birmingham; Miros, Robert H. J.; Stancel, Robert

2013-03-19

A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

Selective Arterial Clamping Versus Hilar Clamping for Minimally Invasive Partial Nephrectomy.

PubMed

Yezdani, Mona; Yu, Sue-Jean; Lee, David I

2016-05-01

Partial nephrectomy has become an accepted treatment of cT1 renal masses as it provides improved long-term renal function compared to radical nephrectomy (Campbell et al. J Urol. 182:1271-9, 2009). Hilar clamping is utilized to help reduce bleeding and improve visibility during tumor resection. However, concern over risk of kidney injury with hilar clamping has led to new techniques to reduce length of warm ischemia time (WIT) during partial nephrectomy. These techniques have progressed over the years starting with early hilar unclamping, controlled hypotension during tumor resection, selective arterial clamping, minimal margin techniques, and off-clamp procedures. Selective arterial clamping has progressed significantly over the years. The main question is what are the exact short- and long-term renal effects from increasing clamp time. Moreover, does it make sense to perform these more time-consuming or more complex procedures if there is no long-term preservation of kidney function? More recent studies have shown no difference in renal function 6 months from surgery when selective arterial clamping or even hilar clamping is employed, although there is short-term improved decline in estimated glomerular filtration rate (eGFR) with selective clamping and off-clamp techniques (Komninos et al. BJU Int. 115:921-8, 2015; Shah et al. 117:293-9, 2015; Kallingal et al. BJU Int. doi: 10.1111/bju.13192, 2015). This paper reviews the progression of total hilar clamping to selective arterial clamping (SAC) and the possible difference its use makes on long-term renal function. SAC may be attempted based on surgeon's decision-making, but may be best used for more complex, larger, more central or hilar tumors and in patients who have renal insufficiency at baseline or a solitary kidney.

Rigid clamp

DOEpatents

Benavides, G.L.; Burt, J.D.

1994-07-12

The invention relates to a clamp mechanism that can be used to attach or temporarily support objects inside of tubular goods. The clamp mechanism can also be modified so that it grips objects. The clamp has a self-centering feature to accommodate out-of-roundness or other internal defections in tubular objects such as pipe. A plurality of clamping shoes are expanded by a linkage which is preferably powered by a motor to contact the inside of a pipe. The motion can be reversed and jaw elements can be connected to the linkage so as to bring the jaws together to grab an object. 12 figs.

Rigid clamp

DOEpatents

Benavides, Gilbert L.; Burt, Jack D.

1994-01-01

The invention relates to a clamp mechanism that can be used to attach or temporarily support objects inside of tubular goods. The clamp mechanism can also be modified so that it grips objects. The clamp has a self-centering feature to accommodate out-of-roundness or other internal defections in tubular objects such as pipe. A plurality of clamping shoes are expanded by a linkage which is preferably powered by a motor to contact the inside of a pipe. The motion can be reversed and jaw elements can be connected to the linkage so as to bring the jaws together to grab an object.

Structural analysis of a eukaryotic sliding DNA clamp-clamp loadercomplex.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowman, Gregory D.; O'Donnell, Mike; Kuriyan, John

2006-06-17

Sliding clamps are ring-shaped proteins that encircle DNA and confer high processivity on DNA polymerases. Here we report the crystal structure of the five-protein clamp loader complex (replication factor-C, RFC) of the yeast Saccharomyces cerevisiae, bound to the sliding clamp (proliferating cell nuclear antigen, PCNA). Tight interfacial coordination of the ATP analogue ATP-?-S by RFC results in a spiral arrangement of the ATPase domains of the clamp loader above the PCNA ring. Placement of a model for primed DNA within the central hole of PCNA reveals a striking correspondence between the RFC spiral and the grooves of the DNA doublemore » helix. This model, in which the clamp loader complex locks onto primed DNA in a screw-cap-like arrangement, provides a simple explanation for the process by which the engagement of primer-template junctions by the RFC:PCNA complex results in ATP hydrolysis and release of the sliding clamp on DNA.« less

Clamp-mount device

NASA Technical Reports Server (NTRS)

Clark, K. H. (Inventor)

1983-01-01

A clamp-mount device is disclosed for mounting equipment to an associated I-beam and the like structural member of the type having oppositely extending flanges wherein the device comprises a base and a pair of oppositely facing clamping members carried diagonally on the base clamping flanges therebetween and having flange receiving openings facing one another. Lock means are carried diagonally by the base opposite the clamping members locking the flanges in the clamping members. A resilient hub is carried centrally of the base engaging and biasing a back side of the flanges maintaining tightly clamped and facilitating use on vertical as well as horizontal members. The base turns about the hub to receive the flanges within the clamping members. Equipment may be secured to the base by any suitable means such as bolts in openings. Slidable gate latches secure the hinged locks in an upright locking position. The resilient hub includes a recess opening formed in the base and a rubber-like pad carried in this opening being depressably and rotatably carried therein.

Force-Measuring Clamp

NASA Technical Reports Server (NTRS)

Nunnelee, Mark (Inventor)

2004-01-01

A precision clamp that accurately measures force over a wide range of conditions is described. Using a full bridge or other strain gage configuration. the elastic deformation of the clamp is measured or detected by the strain gages. Thc strain gages transmit a signal that corresponds to the degree of stress upon the clamp. Thc strain gage signal is converted to a numeric display. Calibration is achieved by ero and span potentiometers which enable accurate measurements by the force-measuring clamp.

Mechanism of opening a sliding clamp

PubMed Central

Douma, Lauren G.; Yu, Kevin K.; England, Jennifer K.

2017-01-01

Abstract Clamp loaders load ring-shaped sliding clamps onto DNA where the clamps serve as processivity factors for DNA polymerases. In the first stage of clamp loading, clamp loaders bind and stabilize clamps in an open conformation, and in the second stage, clamp loaders place the open clamps around DNA so that the clamps encircle DNA. Here, the mechanism of the initial clamp opening stage is investigated. Mutations were introduced into the Escherichia coli β-sliding clamp that destabilize the dimer interface to determine whether the formation of an open clamp loader–clamp complex is dependent on spontaneous clamp opening events. In other work, we showed that mutation of a positively charged Arg residue at the β-dimer interface and high NaCl concentrations destabilize the clamp, but neither facilitates the formation of an open clamp loader–clamp complex in experiments presented here. Clamp opening reactions could be fit to a minimal three-step ‘bind-open-lock’ model in which the clamp loader binds a closed clamp, the clamp opens, and subsequent conformational rearrangements ‘lock’ the clamp loader–clamp complex in a stable open conformation. Our results support a model in which the E. coli clamp loader actively opens the β-sliding clamp. PMID:28973453

Comparison of Battery-Powered and Manual Bone Biopsy Systems for Core Needle Biopsy of Sclerotic Bone Lesions.

PubMed

Cohen, Micah G; McMahon, Colm J; Kung, Justin W; Wu, Jim S

2016-05-01

The purpose of this study was to compare manual and battery-powered bone biopsy systems for diagnostic yield and procedural factors during core needle biopsy of sclerotic bone lesions. A total of 155 consecutive CT-guided core needle biopsies of sclerotic bone lesions were performed at one institution from January 2006 to November 2014. Before March 2012, lesions were biopsied with manual bone drill systems. After March 2012, most biopsies were performed with a battery-powered system and either noncoaxial or coaxial biopsy needles. Diagnostic yield, crush artifact, CT procedure time, procedure radiation dose, conscious sedation dose, and complications were compared between the manual and battery-powered core needle biopsy systems by Fisher exact test and t test. One-way ANOVA was used for subgroup analysis of the two battery-powered systems for procedure time and radiation dose. The diagnostic yield for all sclerotic lesions was 60.0% (93/155) and was significantly higher with the battery-powered system (73.0% [27/37]) than with the manual systems (55.9% [66/118]) (p = 0.047). There was no significant difference between the two systems in terms of crush artifact, procedure time, radiation dose, conscious sedation administered, or complications. In subgroup analysis, the coaxial battery-powered biopsies had shorter procedure times (p = 0.01) and lower radiation doses (p = 0.002) than the coaxial manual systems, but the noncoaxial battery-powered biopsies had longer average procedure times and higher radiation doses than the coaxial manual systems. In biopsy of sclerotic bone lesions, use of a battery-powered bone drill system improves diagnostic yield over use of a manual system.

Diagnostic yield of computed tomography-guided bone biopsy and clinical outcomes of tuberculous and pyogenic spondylitis.

PubMed

Joo, Eun-Jeong; Yeom, Joon-Sup; Ha, Young Eun; Park, So Yeon; Lee, Chong-Suh; Kim, Eun-Sang; Kang, Cheol-In; Chung, Doo-Ryeon; Song, Jae-Hoon; Peck, Kyong Ran

2016-07-01

This study aimed to evaluate the efficacy of computed tomography (CT)-guided bone biopsy for the diagnosis of spinal infection and compared the clinical outcomes between tuberculous and pyogenic spinal infections. The retrospective cohort study included patients who received CT-guided bone biopsy at a tertiary hospital over the 13 years. Among 100 patients, 67 had pyogenic spondylitis and 33 had tuberculous spondylitis. Pathogens were isolated from bone specimens obtained by CT-guided biopsy in 42 cases, with diagnostic yields of 61% (20/33) for tuberculous spondylitis and 33% (22/67) for pyogenic spondylitis. For 36 culture-proven pyogenic cases, Staphylococcus aureus was the most commonly isolated organism. Patients with pyogenic spondylitis more frequently presented with fever accompanied by an increase in inflammatory markers than did those with tuberculosis. Among all patients who underwent surgery, the incidence of late surgery performed one month after diagnosis was higher in patients with tuberculous infection (56.3%) than in those with pyogenic disease (23.3%, p = 0.026). Results obtained by CT-guided bone biopsy contributed to prompt diagnoses of spinal infections, especially those caused by tuberculosis. Despite administration of anti-tuberculous agents, patients with tuberculous spondylitis showed an increased tendency to undergo late surgery.

Direct comparison of the diagnostic yield of ultrasound-assisted Abrams and Tru-Cut needle biopsies for pleural tuberculosis.

PubMed

Koegelenberg, Coenraad Frederik N; Bolliger, Christoph Thomas; Theron, Johan; Walzl, Gerhard; Wright, Colleen Anne; Louw, Mercia; Diacon, Andreas Henri

2010-10-01

Tuberculous pleuritis remains the commonest cause of exudative effusions in areas with a high prevalence of tuberculosis and histological and/or microbiological confirmation on pleural tissue is the gold standard for its diagnosis. Uncertainty remains regarding the choice of closed pleural biopsy needles. This prospective study compared ultrasound-assisted Abrams and Tru-Cut needle biopsies with regard to their diagnostic yield for pleural tuberculosis. 89 patients (54 men) of mean ± SD age 38.7 ± 16.7 years with pleural effusions and a clinical suspicion of tuberculosis were enrolled in the study. Transthoracic ultrasound was performed on all patients, who were then randomly assigned to undergo ≥ 4 Abrams needle biopsies followed by ≥ 4 Tru-Cut needle biopsies or vice versa. Medical thoracoscopy was performed on cases with non-diagnostic closed biopsies. Histological and/or microbiological proof of tuberculosis on any pleural specimen was considered the gold standard for pleural tuberculosis. Pleural tuberculosis was diagnosed in 66 patients, alternative diagnoses were established in 20 patients and 3 remained undiagnosed. Pleural biopsy specimens obtained with Abrams needles contained pleural tissue in 81 patients (91.0%) and were diagnostic for tuberculosis in 54 patients (sensitivity 81.8%), whereas Tru-Cut needle biopsy specimens only contained pleural tissue in 70 patients (78.7%, p=0.015) and were diagnostic in 43 patients (sensitivity 65.2%, p=0.022). Ultrasound-assisted pleural biopsies performed with an Abrams needle are more likely to contain pleura and have a significantly higher diagnostic sensitivity for pleural tuberculosis.

Diagnostic Yield of Transbronchial Biopsy in Comparison to High Resolution Computerized Tomography in Sarcoidosis Cases

PubMed

Akten, H Serpil; Kilic, Hatice; Celik, Bulent; Erbas, Gonca; Isikdogan, Zeynep; Turktas, Haluk; Kokturk, Nurdan

2018-04-25

This study aimed to evaluate the diagnostic yield of fiberoptic bronchoscopic (FOB) transbronchial biopsy and its relation with quantitative findings of high resolution computerized tomography (HRCT). A total of 83 patients, 19 males and 64 females with a mean age of 45.1 years diagnosed with sarcoidosis with complete records of high resolution computerized tomography were retrospectively recruited during the time period from Feb 2005 to Jan 2015. High resolution computerized tomography scans were retrospectively assessed in random order by an experienced observer without knowledge of the bronchoscopic results or lung function tests. According to the radiological staging with HRCT, 2.4% of the patients (n=2) were stage 0, 19.3% (n=16) were stage 1, 72.3% (n=60) were stage 2 and 6.0% (n=5) were stage 3. This study showed that transbronchial lung biopsy showed positive results in 39.7% of the stage I or II sarcoidosis patients who were diagnosed by bronchoscopy. Different high resolution computerized tomography patterns and different scores of involvement did make a difference in the diagnostic accuracy of transbronchial biopsy (p=0.007). Creative Commons Attribution License

Sperm Patch-Clamp

PubMed Central

Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy

2014-01-01

Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465

CT-guided transthoracic needle biopsy: a comparison between automated biopsy gun and fine needle aspiration.

PubMed

Arakawa, H; Nakajima, Y; Kurihara, Y; Niimi, H; Ishikawa, T

1996-07-01

We retrospectively investigated the diagnostic accuracy and complication rate of transthoracic core biopsy using an automated biopsy gun and compared the findings with those of aspiration needle biopsy. Seventy-three patients underwent 74 core biopsy procedures and 50 patients underwent 52 aspiration biopsy procedures. Of these, a final diagnosis was obtained in 107 lesions with surgery or clinical course. Fifteen patients in which a final diagnosis was not obtained were excluded from the study on diagnostic accuracy. Thus, in the study of diagnostic accuracy, 63 core biopsy procedures for 62 lesions are included. Core biopsy was performed with an 18 G cutting needle using an automated biopsy gun. Aspiration biopsy was performed with a 20 G aspiration needle. Core biopsy yielded sufficient material in 57/63 procedures (90.5%). A correct diagnosis was obtained in 36 procedures (85.7%) for malignant leisons and a specific benign diagnosis was obtained in 11 procedures (52.4%). Aspiration biopsy yielded a correct diagnosis in 26 procedures (81.3%) for malignant leisons and in seven (46.7%) for benign lesions. The overall correct diagnosis were 75.8% and 71.7% with core biopsy and aspiration biopsy, respectively. Core biopsy gave a higher predictive rate than that of aspiration biopsy for both benign and malignant lessons (P < 0.02). Pneumothorax occurred in 18/74 (24.3%) patients with core biopsy and in 18/45 (40.0%) patients with aspiration biopsy. Of these, three with core biopsy and two with aspiration biopsy needed tube drainage. The other complication was haemoptysis, which occurred in six patients following core biopsy and in three after aspiration biopsy. All nine cases subsided spontaneously. There were no fatal complications. Core biopsy with a biopsy gun increase the diagnostic accuracy with a higher histologic predictive rate and no obvious additional risk of complications.

Experimental and numerical analysis of clamped joints in front motorbike suspensions

NASA Astrophysics Data System (ADS)

Croccolo, D.; de Agostinis, M.; Vincenzi, N.

2010-06-01

Clamped joints are shaft-hub connections used, as an instance, in front motorbike suspensions to lock the steering plates with the legs and the legs with the wheel pin, by means of one or two bolts. The preloading force, produced during the tightening process, should be evaluated accurately, since it must lock safely the shaft, without overcoming the yielding point of the hub. Firstly, friction coefficients have been evaluated on “ad-hoc designed” specimens, by applying the Design of Experiment approach: the applied tightening torque has been precisely related to the imposed preloading force. Then, the tensile state of clamps have been evaluated both via FEM and by leveraging some design formulae proposed by the Authors as function of the preloading force and of the clamp geometry. Finally, the results have been compared to those given by some strain gauges applied on the tested clamps: the discrepancies between numerical analyses, the design formulae and the experimental results remains under a threshold of 10%.

Ultrasound-guided synovial biopsy

PubMed Central

Sitt, Jacqueline C M; Wong, Priscilla

2016-01-01

Ultrasound-guided needle biopsy of synovium is an increasingly performed procedure with a high diagnostic yield. In this review, we discuss the normal synovium, as well as the indications, technique, tissue handling and clinical applications of ultrasound-guided synovial biopsy. PMID:26581578

The Anion Paradox in Sodium Taste Reception: Resolution by Voltage-Clamp Studies

NASA Astrophysics Data System (ADS)

Ye, Qing; Heck, Gerard L.; Desimone, John A.

1991-11-01

Sodium salts are potent taste stimuli, but their effectiveness is markedly dependent on the anion, with chloride yielding the greatest response. The cellular mechanisms that mediate this phenomenon are not known. This "anion paradox" has been resolved by considering the field potential that is generated by restricted electrodiffusion of the anion through paracellular shunts between taste-bud cells. Neural responses to sodium chloride, sodium acetate, and sodium gluconate were studied while the field potential was voltage-clamped. Clamping at electronegative values eliminated the anion effect, whereas clamping at electropositive potentials exaggerated it. Thus, field potentials across the lingual epithelium modulate taste reception, indicating that the functional unit of taste reception includes the taste cell and its paracellular microenvironment.

Split-tapered joint clamping device

DOEpatents

Olsen, Max J.; Schwartz, Jr., John F.

1988-01-01

This invention relates to a clamping device for removably attaching a tool element to a bracket element wherein a bracket element is disposed in a groove in the tool and a clamping member is disposed in said groove and in engagement with a clamping face of the bracket and a wall of the groove and with the clamping member having pivot means engaging the bracket and about which the clamping member rotates.

Long-Time Choledochal Clamping in Wistar Rats Causes Biliary Obstruction Progressing to Hepatic Fibrosis.

PubMed

Jorge, G D L; Tártaro, R R; Escanhoela, C A F; Boin, I D F S F

2016-09-01

Biliary complications are important causes of morbidity and mortality in patients undergoing hepatic surgery. The aim of the study was to evaluate late liver alterations after a long period of choledochal clamping in Wistar rats. Ten male Wistar rats, weighing 304 grams, anesthetized with sodium thiopental (25 mg/kg) and xylazine (10 mg/kg) intravenously, were distributed into 2 groups: the choledochal clamping group (CCG) and the operation sham group (OSG), with 5 animals each submitted to an abdominal incision. In the CCG, the choledochal was isolated, dissected, and clamped with a microvascular clamp for 40 minutes. After this occlusion time, the clamp was removed and the incision was closed. In the OSG the animals, under normal conditions, were submitted only to anesthesia and laparotomy for choledochal manipulation. In all animals, after the 31st day, a hepatic biopsy was carried out for histology and blood biochemical tests: total bilirubin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase. The animals were euthanized under anesthesia. This research was approved by the Ethics Committee on Animal Use (CEUA, Unicamp, No. 2511-1). In the CCG, 100% of the animals showed bile duct dilatation, ductular proliferation, and portal inflammatory infiltrate; 60% showed regenerative nodule formation; and 80% had porta-porta septa and foci of necrosis, all of which were not found in the OSG. All CCG group biochemical tests had significant increases (P < .05) compared with OSG. Long-time choledochal clamping in Wistar rats caused hepatic dysfunction and biochemical and histological injuries with degrees of distortion to the hepatic architecture. Copyright © 2016 Elsevier Inc. All rights reserved.

Radial wedge flange clamp

DOEpatents

Smith, Karl H.

2002-01-01

A radial wedge flange clamp comprising a pair of flanges each comprising a plurality of peripheral flat wedge facets having flat wedge surfaces and opposed and mating flat surfaces attached to or otherwise engaged with two elements to be joined and including a series of generally U-shaped wedge clamps each having flat wedge interior surfaces and engaging one pair of said peripheral flat wedge facets. Each of said generally U-shaped wedge clamps has in its opposing extremities apertures for the tangential insertion of bolts to apply uniform radial force to said wedge clamps when assembled about said wedge segments.

Comparative Effectiveness of Frame-based, Frameless and Intraoperative MRI Guided Brain Biopsy Techniques

PubMed Central

Lu, Yi; Yeung, Cecil; Radmanesh, Alireza; Wiemann, Robert; Black, Peter M.; Golby, Alexandra J.

2015-01-01

Objective Intraoperative MRI (IoMRI) guided brain biopsy provides a real time visual feedback of the lesion that is sampled during surgery. The objective of the study is to compare the diagnostic yield and safety profiles of ioMRI needle brain biopsy with two traditional brain biopsy methods: frame-based and frameless stereotactic brain biopsies. Methods A retrospective analysis from 288 consecutive needle brain biopsies in 277 patients undergoing stereotactic brain biopsy with any of the three biopsy methods at Brigham and Women's Hospital from 2000 to 2008 was performed. Variables such as age, sex, history of radiation and previous surgery, pathology results, complications and postoperative stays were analyzed. Results Over the course of eight years, 288 brain biopsies were performed. 253 (87.8%) biopsies yielded positive diagnostic tissue. Young age (<40 years), history of brain radiation or surgery were significant negative predictors for a positive biopsy diagnostic yield. Excluding patients with prior radiation or surgeries, no significant difference in diagnostic yield was detected among the three groups, with frame-based, frameless and ioMRI guided needle biopsies yield 96.9%, 91.8% and 89.9% positive diagnostic yield, respectively. 19 biopsies (6.6%) were complicated by serious adverse events. The ioMRI-guided brain biopsy was associated with less serious adverse events and the shortest postoperative hospital stay. Conclusions Frame-based, frameless stereotactic and ioMRI guided brain needle biopsy have comparable diagnostic yield for patients with no prior treatments (either radiation or surgery). IoMRI guided brain biopsy is associated with fewer serious adverse events and shorter hospital stay. PMID:25088233

Diagnostic Yield of Computed Tomography-Guided Coaxial Core Biopsy of Undetermined Masses in the Free Retroperitoneal Space: Single-Center Experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stattaus, Joerg, E-mail: joerg.stattaus@uni-due.de; Kalkmann, Janine, E-mail: janine.kalkmann@uk-essen.de; Kuehl, Hilmar, E-mail: hilmar.kuehl@uni-due.d

2008-09-15

The purpose of this study was to evaluate the diagnostic yield of core biopsy in coaxial technique under guidance of computed tomography (CT) for retroperitoneal masses. We performed a retrospective analysis of CT-guided coaxial core biopsies of undetermined masses in the non-organ-bound retroperitoneal space in 49 patients. In 37 cases a 15-G guidance needle with a 16-G semiautomated core biopsy system, and in 12 cases a 16-G guidance needle with an 18-G biopsy system, was used. All biopsies were technically successful. A small hematoma was seen in one case, but no relevant complication occurred. With the coaxial technique, up tomore » 4 specimens were obtained from each lesion (mean, 2.8). Diagnostic accuracy in differentiation between malignant and benign diseases was 95.9%. A specific histological diagnosis could be established in 39 of 42 malignant lesions (92.9%). Correct subtyping of malignant lymphoma according to the WHO classification was possible in 87.0%. Benign lesions were correctly identified in seven cases, although a specific diagnosis could only be made in conjunction with clinical and radiological information. In conclusion, CT-guided coaxial core biopsy provides safe and accurate diagnosis of retroperitoneal masses. A specific histological diagnosis, which is essential for choosing the appropriate therapy, could be established in most cases of malignancy.« less

Use of the Satinsky clamp for hilar clamping during robotic partial nephrectomy: indications, technique, and multi-center outcomes.

PubMed

Abdullah, Newaj; Rahbar, Haider; Barod, Ravi; Dalela, Deepansh; Larson, Jeff; Johnson, Michael; Mass, Alon; Zargar, Homayoun; Kaouk, Jihad; Allaf, Mohamad; Bhayani, Sam; Stifelman, Michael; Rogers, Craig

2017-03-01

A Satinsky clamp may be a backup option for hilar clamping during robotic partial nephrectomy (RPN) if there are challenges with application of bulldog clamps, but there are potential safety concerns. We evaluate outcomes of RPN using Satinsky vs. bulldog clamps, and provide tips for safe use of the Satinsky as a backup option. Using a multi-center database, we identified 1073 patients who underwent RPN between 2006 and 2013, and had information available about method of hilar clamping (bulldog clamp vs. Satinsky clamp). Patient baseline characteristics, tumor features, and perioperative outcomes were compared between the Satinsky and bulldog clamp groups. A Satinsky clamp was used for hilar clamping in 94 (8.8 %) RPN cases, and bulldog clamps were used in 979 (91.2 %) cases. The use of a Satinsky clamp was associated with greater operative time (198 vs. 175 min, p < 0.001), estimated blood loss (EBL, 200 vs. 100 ml, p < 0.001), warm ischemia time (WIT, 20 vs. 19 min, p = 0.036), transfusion rate (12.8 vs. 4.8 %, p = 0.001), and hospital stay (3 vs. 2 days, p < 0.001). Tumor characteristics and number of renal vessels were similar between groups. There were six intraoperative complications in the Satinsky clamp group, but none were directly related to the Satinsky clamp. On multivariable analysis, the use of the Satinsky clamp was not associated with increase in intraoperative or Clavien ≥3 postoperative complications, positive surgical margin rate or percentage change in estimated glomerular filtration rate. A Satinsky clamp can be a backup option for hilar clamping during challenging RPN cases, but requires careful technique, and was rarely necessary.

Quick action clamp

NASA Technical Reports Server (NTRS)

Calco, Frank S. (Inventor)

1991-01-01

A quick release toggle clamp that utilizes a spring that requires a deliberate positive action for disengagement is presented. The clamp has a sliding bolt that provides a latching mechanism. The bolt is moved by a handle that tends to remain in an engaged position while under tension.

Laser beam guard clamps

DOEpatents

Dickson, Richard K.

2010-09-07

A quick insert and release laser beam guard panel clamping apparatus having a base plate mountable on an optical table, a first jaw affixed to the base plate, and a spring-loaded second jaw slidably carried by the base plate to exert a clamping force. The first and second jaws each having a face acutely angled relative to the other face to form a V-shaped, open channel mouth, which enables wedge-action jaw separation by and subsequent clamping of a laser beam guard panel inserted through the open channel mouth. Preferably, the clamping apparatus also includes a support structure having an open slot aperture which is positioned over and parallel with the open channel mouth.

Fabrication and characterization of a piezoelectric energy harvester with clamped-clamped beams

NASA Astrophysics Data System (ADS)

Cui, Yan; Yu, Menglin; Gao, Shiqiao; Kong, Xiangxin; Gu, Wang; Zhang, Ran; Liu, Bowen

2018-05-01

This work presents a piezoelectric energy harvester with clamped-clamped beams, and it is fabricated with MEMS process. When excited by sinusoidal vibration, the energy harvester has a sharp jumping down phenomenon and the measured frequency responses of the clamped-clamped beams structure show a larger bandwidth which is about 56Hz, more efficient than that with cantilever beams. When the exciting acceleration ac is 12m/s2, the energy harvester achieves to a maximum open-circuit voltage of 94mV on one beam. The load voltage is proportional to the load resistance, and it increased with the increase of load resistance. Connected four beams in series, the output power reaches the maximum value of 730 nW and the optimal load is 15KΩ to one beam.

Closed percutaneous pleural biopsy. A lost art in the new era.

PubMed

Khadadah, Mousa E; Muqim, Abdulaziz T; Al-Mutairi, Abdulla D; Nahar, Ibrahim K; Sharma, Prem N; Behbehani, Nasser H; El-Maradni, Nabeel M

2009-06-01

To assess the association between size and number of biopsy specimens obtained by percutaneous closed pleural biopsy, with overall diagnostic yield in general, and histopathological evidence of tuberculosis pleurisy, in particular. One hundred and forty-three patients, with a high index of clinically having tuberculous pleurisy, were referred to the respiratory division of Mubarak Al-Kabeer Hospital in Kuwait during a 9-year period (January 1999 to December 2007). All subjects with exudative lymphocytic predominant effusion underwent percutaneous closed pleural biopsy, looking for tuberculous granulomas. The clinical diagnosis and pathological characteristics (number and size of biopsy samples) were analyzed. Overall diagnostic yield of percutaneous closed pleural biopsy in all cases was noticed to be 52%. The larger biopsy sample size of 3 mm and more, and the higher number of specimens (> or = 4) were significantly associated with an increased diagnostic yield for tuberculous pleurisy (p=0.007 and 0.047). Obtaining 4 or more biopsy samples, and larger specimens of 3mm and more for histopathological evaluation, through percutaneous pleural biopsy, results in a better diagnostic yield for tuberculous pleurisy.

Molecular mechanism of DNA replication-coupled inactivation of the initiator protein in Escherichia coli: interaction of DnaA with the sliding clamp-loaded DNA and the sliding clamp-Hda complex.

PubMed

Su'etsugu, Masayuki; Takata, Makoto; Kubota, Toshio; Matsuda, Yusaku; Katayama, Tsutomu

2004-06-01

In Escherichia coli, the ATP-DnaA protein initiates chromosomal replication. After the DNA polymerase III holoenzyme is loaded on to DNA, DnaA-bound ATP is hydrolysed in a manner depending on Hda protein and the DNA-loaded form of the DNA polymerase III sliding clamp subunit, which yields ADP-DnaA, an inactivated form for initiation. This regulatory DnaA-inactivation represses extra initiation events. In this study, in vitro replication intermediates and structured DNA mimicking replicational intermediates were first used to identify structural prerequisites in the process of DnaA-ATP hydrolysis. Unlike duplex DNA loaded with sliding clamps, primer RNA-DNA heteroduplexes loaded with clamps were not associated with DnaA-ATP hydrolysis, and duplex DNA provided in trans did not rescue this defect. At least 40-bp duplex DNA is competent for the DnaA-ATP hydrolysis when a single clamp was loaded. The DnaA-ATP hydrolysis was inhibited when ATP-DnaA was tightly bound to a DnaA box-bearing oligonucleotide. These results imply that the DnaA-ATP hydrolysis involves the direct interaction of ATP-DnaA with duplex DNA flanking the sliding clamp. Furthermore, Hda protein formed a stable complex with the sliding clamp. Based on these, we suggest a mechanical basis in the DnaA-inactivation that ATP-DnaA interacts with the Hda-clamp complex with the aid of DNA binding. Copyright Blackwell Publishing Limited

Internal V-Band Clamp

DOEpatents

Vaughn, Mark R.; Hafenrichter, Everett S.; Chapa, Agapito C.; Harris, Steven M.; Martinez, Marcus J.; Baty, Roy S.

2006-02-28

A system for clamping two tubular members together in an end-to-end relationship uses a split ring with a V-shaped outer rim that can engage a clamping surface on each member. The split ring has a relaxed closed state where the ends of the ring are adjacent and the outside diameter of the split ring is less than the minimum inside diameter of the members at their ends. The members are clamped when the split ring is spread into an elastically stretched position where the ring rim is pressed tightly against the interior surfaces of the members. Mechanisms are provided for removing the spreader so the split ring will return to the relaxed state, releasing the clamped members.

(18)F-FDG uptake predicts diagnostic yield of transbronchial biopsy in peripheral lung cancer.

PubMed

Umeda, Yukihiro; Demura, Yoshiki; Anzai, Masaki; Matsuoka, Hiroki; Araya, Tomoyuki; Nishitsuji, Masaru; Nishi, Koichi; Tsuchida, Tatsuro; Sumida, Yasuyuki; Morikawa, Miwa; Ameshima, Shingo; Ishizaki, Takeshi; Kasahara, Kazuo; Ishizuka, Tamotsu

2014-07-01

Recent advances in endobronchial ultrasonography with a guide sheath (EBUS-GS) have enabled better visualization of distal airways, while virtual bronchoscopic navigation (VBN) has been shown useful as a guide to navigate the bronchoscope. However, indications for utilizing VBN and EBUS-GS are not always clear. To clarify indications for a bronchoscopic examination using VBN and EBUS-GS, we evaluated factors that predict the diagnostic yield of a transbronchial biopsy (TBB) procedure for peripheral lung cancer (PLC) lesions. We retrospectively reviewed the charts of 194 patients with 201 PLC lesions (≤3cm mean diameter), and analyzed the association of diagnostic yield of TBB with [(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) positron emission tomography and chest computed tomography (CT) findings. The diagnostic yield of TBB using VBN and EBUS-GS was 66.7%. High maximum standardized uptake value (SUVmax), positive bronchus sign, and ground-glass opacity component shown on CT were all significant predictors of diagnostic yield, while multivariate analysis showed only high (18)F-FDG uptake (SUVmax ≥2.8) and positive bronchus sign as significant predictors. Diagnostic yield was higher for PLC lesions with high (18)F-FDG uptake (SUVmax ≥2.8) and positive bronchus sign (84.6%) than for those with SUVmax <2.8 and negative bronchus sign (33.3%). High (18)F-FDG uptake was also correlated with tumor invasiveness. High (18)F-FDG uptake predicted the diagnostic yield of TBB using VBN and EBUS-GS for PLC lesions. (18)F-FDG uptake and bronchus sign may indicate for the accurate application of bronchoscopy with those modalities for diagnosing PLC. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Lifting clamp positively grips structural shapes

NASA Technical Reports Server (NTRS)

Reinhardt, E. C.

1966-01-01

Welded steel clamps securely grip structural shapes of various sizes for crane operations. The clamp has adjustable clamping jaws and screw-operated internal v-jaws and provides greater safety than hoisting slings presently used. The structural member can be rotated in any manner, angle, or direction without being released by the clamp.

Incremental yield of dysplasia detection in Barrett's esophagus using volumetric laser endomicroscopy with and without laser marking compared with a standardized random biopsy protocol.

PubMed

Alshelleh, Mohammad; Inamdar, Sumant; McKinley, Matthew; Stewart, Molly; Novak, Jeffrey S; Greenberg, Ronald E; Sultan, Keith; Devito, Bethany; Cheung, Mary; Cerulli, Maurice A; Miller, Larry S; Sejpal, Divyesh V; Vegesna, Anil K; Trindade, Arvind J

2018-02-02

Volumetric laser endomicroscopy (VLE) is a new wide-field advanced imaging technology for Barrett's esophagus (BE). No data exist on incremental yield of dysplasia detection. Our aim is to report the incremental yield of dysplasia detection in BE using VLE. This is a retrospective study from a prospectively maintained database from 2011 to 2017 comparing the dysplasia yield of 4 different surveillance strategies in an academic BE tertiary care referral center. The groups were (1) random biopsies (RB), (2) Seattle protocol random biopsies (SP), (3) VLE without laser marking (VLE), and (4) VLE with laser marking (VLEL). A total of 448 consecutive patients (79 RB, 95 SP, 168 VLE, and 106 VLEL) met the inclusion criteria. After adjusting for visible lesions, the total dysplasia yield was 5.7%, 19.6%, 24.8%, and 33.7%, respectively. When compared with just the SP group, the VLEL group had statistically higher rates of overall dysplasia yield (19.6% vs 33.7%, P = .03; odds ratio, 2.1, P = .03). Both the VLEL and VLE groups had statistically significant differences in neoplasia (high-grade dysplasia and intramucosal cancer) detection compared with the SP group (14% vs 1%, P = .001 and 11% vs 1%, P = .003). A surveillance strategy involving VLEL led to a statistically significant higher yield of dysplasia and neoplasia detection compared with a standard random biopsy protocol. These results support the use of VLEL for surveillance in BE in academic centers. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Detachable clamps for minimal access surgery.

PubMed

Frank, T; Willetts, G J; Cuschieri, A

1995-01-01

A detachable clamp and applicator have been developed for use in minimal access surgical operations involving hollow visceral transection and anastomosis. The clamp has parallel jaws which ensure uniform distribution of the occlusive force. Following application on the bowel, the clamp is released from the applicator, thus freeing the access port. On completion of the anastomosis, the clamp is docked to the applicator, its jaws opened for release from the bowel and then closed prior to removal. The jaws of the clamp are kept closed by a pseudoelastic nickel-titanium (NiTi) alloy spring which imparts advantageous force characteristics when compared to stainless steel. The excellent holding and atraumatic characteristics of the detachable clamp have been confirmed by use in laparoscopic and thoracoscopic surgery on the gastrointestinal tract.

Feasibility and Diagnostic Yield of Endoscopic Ultrasonography-Guided Fine Needle Biopsy With a New Core Biopsy Needle Device in Patients With Gastric Subepithelial Tumors

PubMed Central

Lee, Minju; Min, Byung-Hoon; Lee, Hyuk; Ahn, Sangjeong; Lee, Jun Haeng; Rhee, Poong-Lyul; Kim, Jae J.; Sohn, Tae Sung; Kim, Sung; Kim, Kyoung-Mee

2015-01-01

Abstract As treatment decisions for patients with gastric subepithelial tumors (SETs) largely depend on the histopathologic diagnosis, noninvasive and effective tissue acquisition methods are definitely required for proper management of gastric SETs. Recently, a new endoscopic ultrasonography-guided fine needle biopsy (EUS-FNB) device with ProCore reverse bevel technology was developed. We aimed to elucidate the feasibility and diagnostic yield of EUS-FNB with this new core biopsy needle device in patients with gastric SETs. A prospectively maintained database was retrospectively reviewed to identify consecutive patients who underwent EUS-FNB with a 22-gauge ProCore needle for gastric SETs 2 cm or larger. The main outcome measurement was the diagnostic yield of EUS-FNB. Procedure results were categorized into diagnostic, suggestive, or nondiagnostic. Of the 43 patients, needle punctures were successful in all cases irrespective of tumor location. EUS-FNB procedure results were diagnostic in 86.0%, suggestive in 4.7%, and nondiagnostic in 9.3% of cases, respectively. The diagnostic yield was the highest in fundus (100.0%), followed by body (89.5%), cardia (83.3%), and antrum (50.0%). All 18 patients with cardiac SET were finally diagnosed to have leiomyoma, and 16 patients with diagnostic or suggestive results avoided surgery. A heterogeneous echo pattern on EUS was found in 33.3% of cases with nondiagnostic or suggestive results and in 5.4% with diagnostic results. In multivariate analysis, no independent predictor of unsuccessful EUS-FNB with nondiagnostic or suggestive results was identified. Agreement between EUS-FNB and surgical pathology was 100% with respect to the diagnosis of gastrointestinal stromal tumor. However, there was a significant discrepancy in mitotic counts observed between the EUS-FNB and surgical specimens in patients with gastrointestinal stromal tumor. There were no significant procedure-related adverse events during and after the

[Diagnostic rentability of close pleural biopsy: Tru-cut vs. Cope].

PubMed

Valdez-López, Héctor Glenn; Cano-Rodríguez, Alma Iris; Montemayor-Chapa, Mario; Castillo-Sánchez, Juan Francisco

2018-01-01

The prevalence of pleural effusion in Mexico is over 400 per 100 000 inhabitants. The etiology is infectious in 45.7% and neoplastic in 32.6%. Closed pleural biopsy sensibility is 48-70% in cancer and 50-59% in tuberculosis using Cope or Abrams needle. In 1989, Tru-cut needle biopsy was described in a small study for massive pleural effusions with a sensibility of 86%. Our Institute has a wide experience with this infrequently procedure with reliable results than using Cope needle. Diagnostic yield should be evaluated. We aimed to evaluate the diagnostic yield of Tru-cut vs. standard Cope biopsy in the histopathological diagnosis of pleural effusion. Experimental, not blinded, analytical, cross-sectional study. We studied 44 patients (24 male and 20 female) with exudative pleural effusion over a period of 14 months. Every patient underwent four Tru-cut and four Cope needle biopsies. The diagnostic yield of both methods was compared. The mean age of patients was 61.4 ± 12.2 years. The diagnosis was achieved in 25 (57%) of patients using Tru-cut and 22 (50%) of patients using Cope's closed pleural biopsy. The diagnostic value was not significantly higher (p = 0.41). The most common diagnoses were adenocarcinoma (20.5%), mesothelioma (15.9%) and tuberculosis (15.9%). The diagnostic yield of Tru-cut needle biopsy is slightly higher than Cope pleural biopsy, very similar to that reported previously. The experience in this procedure is an advantage in our clinical practice.

Sound absorption by clamped poroelastic plates.

PubMed

Aygun, H; Attenborough, K

2008-09-01

Measurements and predictions have been made of the absorption coefficient and the surface acoustic impedance of poroelastic plates clamped in a large impedance tube and separated from the rigid termination by an air gap. The measured and predicted absorption coefficient and surface impedance spectra exhibit low frequency peaks. The peak frequencies observed in the absorption coefficient are close to those predicted and measured in the deflection spectra of the clamped poroelastic plates. The influences of the rigidity of the clamping conditions and the width of the air gap have been investigated. Both influences are found to be important. Increasing the rigidity of clamping reduces the low frequency absorption peaks compared with those measured for simply supported plates or plates in an intermediate clamping condition. Results for a closed cell foam plate and for two open cell foam plates made from recycled materials are presented. For identical clamping conditions and width of air gap, the results for the different materials differ as a consequence mainly of their different elasticity, thickness, and cell structure.

Management of umbilical cord clamping.

PubMed

Webbon, Lucy

2013-02-01

The Royal College of Midwives (RCM) has updated its third stage of labour guidelines (RCM 2012) to be clearly supportive of a delay in umbilical cord clamping, although specific guidance on timing is yet to be announced. It is therefore imperative that both midwives and student midwives understand and are able to integrate delaying into their practice, as well as communicating to women the benefits; only in this way can we give women fully informed choices on this aspect of care. The main benefit of delayed cord clamping is the protection it can provide in reducing childhood anaemia, which is a major issue, especially in poorer countries. A review of the evidence found no risks linked to delayed clamping, and no evidence that it cannot be used in combination with the administration of uterotonic drugs. Delayed cord clamping can be especially beneficial for pre term and compromised babies.

Robotic multi-well planar patch-clamp for native and primary mammalian cells

PubMed Central

Milligan, Carol J; Li, Jing; Sukumar, Piruthivi; Majeed, Yasser; Dallas, Mark L; English, Anne; Emery, Paul; Porter, Karen E; Smith, Andrew M; McFadzean, Ian; Beccano-Kelly, Dayne; Bahnasi, Yahya; Cheong, Alex; Naylor, Jacqueline; Zeng, Fanning; Liu, Xing; Gamper, Nikita; Jiang, Lin-Hua; Pearson, Hugh A; Peers, Chris; Robertson, Brian; Beech, David J

2009-01-01

Multi-well robotic planar patch-clamp has become common in drug development and safety programmes because it enables efficient and systematic testing of compounds against ion channels during voltage-clamp. It has not, however, been adopted significantly in other important areas of ion channel research, where conventional patch-clamp remains the favoured method. Here we show the wider potential of the multi-well approach with the capability for efficient intracellular solution exchange, describing protocols and success rates for recording from a range of native and primary mammalian cells derived from blood vessels, arthritic joints, and the immune and central nervous systems. The protocol involves preparing a suspension of single cells to be dispensed robotically into 4-8 microfluidic chambers each containing a glass chip with a small aperture. Under automated control, giga-seals and whole-cell access are achieved followed by pre-programmed routines of voltage paradigms and fast extracellular or intracellular solution exchange. Recording from 48 chambers usually takes 1-6 hr depending on the experimental design and yields 16-33 cell recordings. PMID:19197268

A clamped rectangular plate containing a crack

NASA Technical Reports Server (NTRS)

Tang, R.; Erdogan, F.

1985-01-01

The general problem of a rectangular plate clamped along two parallel sides and containing a crack parallel to the clamps is considered. The problem is formulated in terms of a system of singular integral equations and the asymptotic behavior of the stress state near the corners is investigated. Numerical examples are considered for a clamped plate without a crack and with a centrally located crack, and the stress intensity factors and the stresses along the clamps are calculated.

Micromachined patch-clamp apparatus

DOEpatents

Okandan, Murat

2012-12-04

A micromachined patch-clamp apparatus is disclosed for holding one or more cells and providing electrical, chemical, or mechanical stimulation to the cells during analysis with the patch-clamp technique for studying ion channels in cell membranes. The apparatus formed on a silicon substrate utilizes a lower chamber formed from silicon nitride using surface micromachining and an upper chamber formed from a molded polymer material. An opening in a common wall between the chambers is used to trap and hold a cell for analysis using the patch-clamp technique with sensing electrodes on each side of the cell. Some embodiments of the present invention utilize one or more electrostatic actuators formed on the substrate to provide mechanical stimulation to the cell being analyzed, or to provide information about mechanical movement of the cell in response to electrical or chemical stimulation.

Cell-Detection Technique for Automated Patch Clamping

NASA Technical Reports Server (NTRS)

McDowell, Mark; Gray, Elizabeth

2008-01-01

A unique and customizable machinevision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify good and bad cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost. The present technique involves the utilization of cell-feature metrics to accurately make decisions on the degree to which individual cells are "good" or "bad" candidates for patch clamping. These metrics include position coordinates (x,y) in the image plane, major-axis length, minor-axis length, area, elongation, roundness, smoothness, angle of orientation, and degree of inclusion in the field of view. The present technique does not require any special hardware beyond commercially available, off-the-shelf patch-clamping hardware: A standard patchclamping microscope system with an attached CCD camera, a personal computer with an imagedata- processing board, and some experience in utilizing imagedata- processing software are all that are needed. A cell image is first captured by the microscope CCD camera and image-data-processing board, then the image

Multiple Biopsies and Detection of Cervical Cancer Precursors at Colposcopy

PubMed Central

Wentzensen, Nicolas; Walker, Joan L.; Gold, Michael A.; Smith, Katie M.; Zuna, Rosemary E.; Mathews, Cara; Dunn, S. Terence; Zhang, Roy; Moxley, Katherine; Bishop, Erin; Tenney, Meaghan; Nugent, Elizabeth; Graubard, Barry I.; Wacholder, Sholom; Schiffman, Mark

2015-01-01

Purpose Women with abnormal cervical cancer screening results are referred to colposcopy and biopsy for diagnosis of cervical cancer precursors (high-grade squamous intraepithelial lesions [HSILs]). Colposcopy with a single biopsy can miss identification of HSILs. No systematic study has quantified the improved detection of HSIL by taking multiple lesion-directed biopsies. Methods The Biopsy Study was an observational study of 690 women referred to colposcopy after abnormal cervical cancer screening results. Up to four directed biopsies were taken from distinct acetowhite lesions and ranked by colposcopic impression. A nondirected biopsy of a normal-appearing area was added if fewer than four directed biopsies were taken. HSIL identified by any biopsy was the reference standard of disease used to evaluate the incremental yield and sensitivity of multiple biopsies. Results In the overall population, sensitivities for detecting HSIL increased from 60.6% (95% CI, 54.8% to 66.6%) from a single biopsy to 85.6% (95% CI, 80.3% to 90.2%) after two biopsies and to 95.6% (95% CI, 91.3% to 99.2%) after three biopsies. A significant increase in sensitivity of multiple biopsies was observed in all subgroups. The highest increase in yield of HSIL was observed for women with a high-grade colposcopic impression, HSIL cytology, and human papillomavirus (HPV) type 16 positivity. Only 2% of all HSILs diagnosed in the participants were detected by biopsies of normal-appearing transformation zone. Conclusion Collection of additional lesion-directed biopsies during colposcopy increased detection of histologic HSIL, regardless of patient characteristics. Taking additional biopsies when multiple lesions are present should become the standard practice of colposcopic biopsy. PMID:25422481

Clamp force and alignment checking device

DOEpatents

Spicer, John Patrick; Cai, Wayne W.; Chakraborty, Debejyo; Mink, Keith

2017-04-11

A check fixture measures a total clamp force applied by a welder device. The welder device includes a welding horn having a plurality of weld pads and welding anvil having a plurality of weld pads. The check fixture includes a base member operatively supporting a plurality of force sensors. The base member and the force sensors are received between the weld pads of the welding horn and the anvil pads of the welding anvil. Each force sensor is configured to measure an individual clamp force applied thereto by corresponding weld and anvil pads when the base member is received between the welding horn and the welding anvil and the welder device is in the clamped position. The individual clamp forces are used to determine whether the weld and/or anvil pads are worn or misaligned.

Advanced motor driven clamped borehole seismic receiver

DOEpatents

Engler, Bruce P.; Sleefe, Gerard E.; Striker, Richard P.

1993-01-01

A borehole seismic tool including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric meter in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.

Plastic Clamp Retains Clevis Pin

NASA Technical Reports Server (NTRS)

Cortes, R. G.

1983-01-01

Plastic clamp requires no special installation or removal tools. Clamp slips easily over end of pin. Once engaged in groove, holds pin securely. Installed and removed easily without special tools - screwdriver or putty knife adequate for prying out of groove. Used to retain bearings, rollers pulleys, other parts that rotate. Applications include slowly and intermittently rotating parts in appliances.

Piezoresistive cantilever force-clamp system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Sung-Jin; Petzold, Bryan C.; Pruitt, Beth L.

2011-04-15

We present a microelectromechanical device-based tool, namely, a force-clamp system that sets or ''clamps'' the scaled force and can apply designed loading profiles (e.g., constant, sinusoidal) of a desired magnitude. The system implements a piezoresistive cantilever as a force sensor and the built-in capacitive sensor of a piezoelectric actuator as a displacement sensor, such that sample indentation depth can be directly calculated from the force and displacement signals. A programmable real-time controller operating at 100 kHz feedback calculates the driving voltage of the actuator. The system has two distinct modes: a force-clamp mode that controls the force applied to amore » sample and a displacement-clamp mode that controls the moving distance of the actuator. We demonstrate that the system has a large dynamic range (sub-nN up to tens of {mu}N force and nm up to tens of {mu}m displacement) in both air and water, and excellent dynamic response (fast response time, <2 ms and large bandwidth, 1 Hz up to 1 kHz). In addition, the system has been specifically designed to be integrated with other instruments such as a microscope with patch-clamp electronics. We demonstrate the capabilities of the system by using it to calibrate the stiffness and sensitivity of an electrostatic actuator and to measure the mechanics of a living, freely moving Caenorhabditis elegans nematode.« less

Cable clamp bolt fixture facilitates assembly in close quarters

NASA Technical Reports Server (NTRS)

Sunderland, G. H.

1967-01-01

Cable clamp bolt holding fixture facilitates forming of electrical cable runs in limited equipment space. The fixture engages the threads of the short clamp bolt through the clamp and maintains tension against clamp tendency to open while the operator installs the nut without difficulty.

Biopsy of CT-Occult Bone Lesions Using Anatomic Landmarks for CT Guidance.

PubMed

Hillen, Travis J; Talbert, Robert J; Friedman, Michael V; Long, Jeremiah R; Jennings, Jack W; Wessell, Daniel E; Baker, Jonathan C

2017-07-01

The purpose of this study is to evaluate the histopathologic diagnostic yield, sample size, procedural time, and dose-length product (DLP) for the biopsy of CT-occult lesions found at MRI or PET or both. A retrospective review of our radiology information system for biopsies of CT-occult lesions using CT guidance from January 1, 2010, through December 31, 2014, was performed and compared with a selection of CT-guided biopsies of CT-evident bone lesions during the same period. The data were then evaluated for diagnostic yield of histopathologic diagnosis, procedural time, use of sedation medication, DLP, and size of specimens obtained. A total of 30 CT-occult biopsies met the inclusion criteria. Twenty-seven of those biopsies had results that were concordant with the patient's primary histopathologic diagnosis, imaging findings, and clinical course. In the CT-evident lesion group, concordant histopathologic abnormalities were identified in 27 of 30 patients. There was a statistically significant increase in number of samples obtained for the CT-evident lesions compared with CT-occult lesions. There was no statistically significant difference in total specimen length, DLP, number of CT scans, procedural time, or use of sedation medication between the CT-occult and CT-evident biopsy groups. Biopsy of CT-occult lesions using anatomic landmarks achieves diagnostic yields similar to those for CT-guided biopsy of CT-evident lesions.

Advanced motor driven clamped borehole seismic receiver

DOEpatents

Engler, B.P.; Sleefe, G.E.; Striker, R.P.

1993-02-23

A borehole seismic tool is described including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric motor in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.

Parotid gland biopsy and /sup 67/Ga imaging correlation in systemic sarcoidosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brantley, S.D.; Orzel, J.A.; Weiland, F.L.

1987-03-01

We correlated the results of parotid gland biopsy, chest roentgenograms, and gallium citrate scintigraphy in 24 patients evaluated for possible systemic sarcoidosis. Of 19 patients ultimately proven to have sarcoidosis, 11 (57.9 percent) had positive parotid gland biopsy. The yield of parotid gland biopsy in patients with abnormal gallium parotid activity was only marginally higher (64.7 percent). Abnormal parotid gland uptake of gallium citrate was seen in 17 of these 19 patients (89.5 percent) and was always associated with abnormal lung or perihilar activity. The parotid gland biopsy is a useful technique for obtaining the tissue diagnosis of sarcoidosis; however,more » gallium scintigraphy should not be performed to select patients as this will only marginally increase the biopsy yield.« less

Ultrasound-guided synovial Tru-cut biopsy: indications, technique, and outcome in 111 cases.

PubMed

Sitt, Jacqueline C M; Griffith, James F; Lai, Fernand M; Hui, Mamie; Chiu, K H; Lee, Ryan K L; Ng, Alex W H; Leung, Jason

2017-05-01

To investigate the diagnostic performance of ultrasound-guided synovial biopsy. Clinical notes, pathology and microbiology reports, ultrasound and other imaging studies of 100 patients who underwent 111 ultrasound-guided synovial biopsies were reviewed. Biopsies were compared with the final clinical diagnosis established after synovectomy (n = 43) or clinical/imaging follow-up (n = 57) (mean 30 months). Other than a single vasovagal episode, no complication of synovial biopsy was encountered. One hundred and seven (96 %) of the 111 biopsies yielded synovium histologically. Pathology ± microbiology findings for these 107 conclusive biopsies comprised synovial tumour (n = 30, 28 %), synovial infection (n = 18, 17 %), synovial inflammation (n = 45, 42 %), including gouty arthritis (n = 3), and no abnormality (n = 14, 13 %). The accuracy, sensitivity, and specificity of synovial biopsy was 99 %, 97 %, and 100 % for synovial tumour; 100 %, 100 %, and 100 % for native joint infection; and 78 %, 45 %, and 100 % for prosthetic joint infection. False-negative synovial biopsy did not seem to be related to antibiotic therapy. Ultrasound-guided Tru-cut synovial biopsy is a safe and reliable technique with a high diagnostic yield for diagnosing synovial tumour and also, most likely, for joint infection. Regarding joint infection, synovial biopsy of native joints seems to have a higher diagnostic yield than that for infected prosthetic joints. • Ultrasound-guided Tru-cut synovial biopsy has high accuracy (99 %) for diagnosing synovial tumour. • It has good accuracy, sensitivity, and high specificity for diagnosis of joint infection. • Synovial biopsy of native joints works better than biopsy of prosthetic joints. • A negative synovial biopsy culture from a native joint largely excludes septic arthritis. • Ultrasound-guided Tru-cut synovial biopsy is a safe and well-tolerated procedure.

21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures. (b...

Patch-clamp amplifiers on a chip

PubMed Central

Weerakoon, Pujitha; Culurciello, Eugenio; Yang, Youshan; Santos-Sacchi, Joseph; Kindlmann, Peter J.; Sigworth, Fred J.

2010-01-01

We present the first, fully-integrated, two-channel implementation of a patch-clamp measurement system. With this “PatchChip” two simultaneous whole-cell recordings can be obtained with rms noise of 8 pA in a 10 kHz bandwidth. The capacitance and series-resistance of the electrode can be compensated up to 10 pF and 100 MΩ respectively under computer control. Recordings of hERG and Nav 1.7 currents demonstrate the system's capabilities, which are on par with large, commercial patch-clamp instrumentation. By reducing patch-clamp amplifiers to a millimeter size micro-chip, this work paves the way to the realization of massively-parallel, high-throughput patch-clamp systems for drug screening and ion-channel research. The PatchChip is implemented in a 0.5 μm silicon-on-sapphire process; its size is 3 × 3 mm2 and the power consumption is 5 mW per channel with a 3.3 V power supply. PMID:20637803

Breast epithelium procurement from stereotactic core biopsy washings: flow cytometry-sorted cell count analysis.

PubMed

Stoler, Daniel L; Stewart, Carleton C; Stomper, Paul C

2002-02-01

Molecular studies of breast lesions have been constrained by difficulties in procuring adequate tissues for analyses. Standard procedures are restricted to larger, palpable masses or the use of paraffin-embedded materials, precluding facile procurement of fresh specimens of early lesions. We describe a study to determine the yield and characteristics of sorted cell populations retrieved in core needle biopsy specimen rinses from a spectrum of breast lesions. Cells from 114 consecutive stereotactic core biopsies of mammographic lesions released into saline washes were submitted for flow cytometric analysis. For each specimen, epithelial cells were separated from stromal and blood tissue based on the presence of cytokeratin 8 and 18 markers. Epithelial cell yields based on pathological diagnoses of the biopsy specimen, patient age, and mammographic appearance of the lesion were determined. Biopsies containing malignant lesions yielded significantly higher numbers of cells than were obtained from benign lesion biopsies. Significantly greater cell counts were observed from lesions from women age 50 or above compared with those of younger women. Mammographic density surrounding the biopsy site, the mammographic appearance of the lesion, and the number of cores taken at the time of biopsy appeared to have little effect on the yield of epithelial cells. We demonstrate the use of flow cytometric sorting of stereotactic core needle biopsy washes from lesions spanning the spectrum of breast pathology to obtain epithelial cells in sufficient numbers to meet the requirements of a variety of molecular and genetic analyses.

Combination Space Station Handrail Clamp and Pointing Device

NASA Technical Reports Server (NTRS)

Hughes, Stephen J. (Inventor)

1999-01-01

A device for attaching an experiment carrier to a space station handrail is provided. The device has two major components, a clamping mechanism for attachment to a space station handrail, and a pointing carrier on which an experiment package can be mounted and oriented. The handrail clamp uses an overcenter mechanism and the carrier mechanism uses an adjustable preload ball and socket for carrier positioning. The handrail clamp uses a stack of disk springs to provide a spring loaded button. This configuration provides consistent clamping force over a range of possible handrail thicknesses. Three load points are incorporated in the clamping mechanism thereby spreading the clamping load onto three separate points on the handrail. A four bar linkage is used to provide for a single actuation lever for all three load points. For additional safety, a secondary lock consisting of a capture plate and push lock keeps the clamp attached to the handrail in the event of main clamp failure. For the carrier positioning mechanism, a ball in a spring loaded socket uses friction to provide locking torque; however. the ball and socket are torque limited so that the ball ran slip under kick loads (125 pounds or greater). A lead screw attached to disk spring stacks is used to provide an adjustable spring force on the socket. A locking knob is attached to the lead screw to allow for hand manipulation of the lead screw.

Mechanics of wafer bonding: Effect of clamping

NASA Astrophysics Data System (ADS)

Turner, K. T.; Thouless, M. D.; Spearing, S. M.

2004-01-01

A mechanics-based model is developed to examine the effects of clamping during wafer bonding processes. The model provides closed-form expressions that relate the initial geometry and elastic properties of the wafers to the final shape of the bonded pair and the strain energy release rate at the interface for two different clamping configurations. The results demonstrate that the curvature of bonded pairs may be controlled through the use of specific clamping arrangements during the bonding process. Furthermore, it is demonstrated that the strain energy release rate depends on the clamping configuration and that using applied loads usually leads to an undesirable increase in the strain energy release rate. The results are discussed in detail and implications for process development and bonding tool design are highlighted.

21 CFR 876.5160 - Urological clamp for males.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Urological clamp for males. 876.5160 Section 876...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5160 Urological clamp for males. (a) Identification. A urological clamp for males is a device used to close the urethra of a male to...

Forceps biopsy and suction catheter for sampling in pulmonary nodules and infiltrates.

PubMed

Peschke, Antje; Wiedemann, Bärbel; Höffken, Gert; Koschel, Dirk

2012-06-01

Transbronchial lung biopsy with forceps is a standard procedure in bronchoscopic tissue sampling. Suction catheter aspiration is another technique, but it is not widely known and almost no data exist regarding its diagnostic efficiency. 272 patients were included in a prospective and randomised study between February 2007 and October 2009. All were referred for bronchoscopic evaluation of pulmonary nodules/masses or infiltrates. We compared the diagnostic yield of forceps biopsy and suction catheter aspiration for a definite diagnosis and looked at whether such a diagnosis depends on the underlying pulmonary change. All patients underwent bronchoscopy with forceps biopsy and catheter aspiration. A definitive diagnosis was reached in a total of 183 (67.3%) patients, with catheter aspiration in 140 (51.5%) patients and with forceps biopsy in 136 (50.0%) patients. In 90 (33.1%) patients, a definite diagnosis could only be reached with the combination of both techniques. The diagnostic yield of forceps biopsy was better than catheter aspiration in infiltrates (p = 0.027), but was no different in nodules or masses (p = 0.09). Suction catheter aspiration is a useful technique of bronchoscopic tissue sampling. The combination of catheter aspiration and forceps biopsy results in a higher diagnostic yield than either method used alone.

Clinical and prognostic significance of muscle biopsy in sarcoidosis.

PubMed

Yanardag, Halil; Tetikkurt, Cuneyt; Bilir, Muammer

2018-04-30

The main objective of this study was to evaluate the influence of muscle involvement on the clinical features, prognostic outcome, extrapulmonary organ, and endobronchial involvement in sarcoidosis patients. The second aim was to assess the diagnostic yield of muscle biopsy for the histopathologic identification of sarcoidosis.  Fifty sarcoidosis patients participated in the study. The patients were classified into two groups according to the histopathologic presence of non-caseating granulomatous inflammatory pattern of the muscle biopsy samples and were evaluated retrospectively in regard to clinical features, prognosis, extrapulmonary, and endobronchial disease involvement. Pathologic examination of the muscle biopsy samples revealed non-caseating granulomas in eighteen and myositis in seven patients compatible with sarcoidosis. The diagnostic yield of muscle biopsy for demonstrating non-caseating granulomatous inflammation was fifty percent. Patients with muscle sarcoidosis showed a worse prognosis and a more severe extrapulmonary organ involvement than the patients without muscle disease. Muscle biopsy was not statistically significant to delineate diffuse endobronchial involvement while it was suggestive for endobronchial disease clinically. The results of our study reveal that muscle biopsy appears to be a useful diagnostic tool along with its safety and easy clinical applicability. It is a rewarding utility to predict the prognostic outcome and extrapulmonary involvement in sarcoidosis patients. Positive biopsy on the other hand confirms the identification of sarcoidosis in patients with single organ involvement carrying an equivocal diagnostic clinical pattern. Muscle biopsy may be considered as the initial step for the final diagnosis of sarcoidosis in such cases.

Cryobiopsy: should this be used in place of endobronchial forceps biopsies?

PubMed

Rubio, Edmundo R; le, Susanti R; Whatley, Ralph E; Boyd, Michael B

2013-01-01

Forceps biopsies of airway lesions have variable yields. The yield increases when combining techniques in order to collect more material. With the use of cryotherapy probes (cryobiopsy) larger specimens can be obtained, resulting in an increase in the diagnostic yield. However, the utility and safety of cryobiopsy with all types of lesions, including flat mucosal lesions, is not established. Demonstrate the utility/safety of cryobiopsy versus forceps biopsy to sample exophytic and flat airway lesions. Teaching hospital-based retrospective analysis. Retrospective analysis of patients undergoing cryobiopsies (singly or combined with forceps biopsies) from August 2008 through August 2010. Statistical Analysis. Wilcoxon signed-rank test. The comparative analysis of 22 patients with cryobiopsy and forceps biopsy of the same lesion showed the mean volumes of material obtained with cryobiopsy were significantly larger (0.696 cm(3) versus 0.0373 cm(3), P = 0.0014). Of 31 cryobiopsies performed, one had minor bleeding. Cryopbiopsy allowed sampling of exophytic and flat lesions that were located centrally or distally. Cryobiopsies were shown to be safe, free of artifact, and provided a diagnostic yield of 96.77%. Cryobiopsy allows safe sampling of exophytic and flat airway lesions, with larger specimens, excellent tissue preservation and high diagnostic accuracy.

Cryobiopsy: Should This Be Used in Place of Endobronchial Forceps Biopsies?

PubMed Central

Rubio, Edmundo R.; le, Susanti R.; Whatley, Ralph E.; Boyd, Michael B.

2013-01-01

Forceps biopsies of airway lesions have variable yields. The yield increases when combining techniques in order to collect more material. With the use of cryotherapy probes (cryobiopsy) larger specimens can be obtained, resulting in an increase in the diagnostic yield. However, the utility and safety of cryobiopsy with all types of lesions, including flat mucosal lesions, is not established. Aims. Demonstrate the utility/safety of cryobiopsy versus forceps biopsy to sample exophytic and flat airway lesions. Settings and Design. Teaching hospital-based retrospective analysis. Methods. Retrospective analysis of patients undergoing cryobiopsies (singly or combined with forceps biopsies) from August 2008 through August 2010. Statistical Analysis. Wilcoxon signed-rank test. Results. The comparative analysis of 22 patients with cryobiopsy and forceps biopsy of the same lesion showed the mean volumes of material obtained with cryobiopsy were significantly larger (0.696 cm3 versus 0.0373 cm3, P = 0.0014). Of 31 cryobiopsies performed, one had minor bleeding. Cryopbiopsy allowed sampling of exophytic and flat lesions that were located centrally or distally. Cryobiopsies were shown to be safe, free of artifact, and provided a diagnostic yield of 96.77%. Conclusions. Cryobiopsy allows safe sampling of exophytic and flat airway lesions, with larger specimens, excellent tissue preservation and high diagnostic accuracy. PMID:24066296

Renal functional and perioperative outcomes of off-clamp versus clamped robot-assisted partial nephrectomy: matched cohort study.

PubMed

Tanagho, Youssef S; Bhayani, Sam B; Sandhu, Gurdarshan S; Vaughn, Nicholas P; Nepple, Kenneth G; Figenshau, R Sherburne

2012-10-01

To evaluate the potential benefit of performing off-clamp robot-assisted partial nephrectomy as it relates to renal functional outcomes, while assessing the safety profile of this unconventional surgical approach. Twenty-nine patients who underwent off-clamp robot-assisted partial nephrectomy for suspected renal cell carcinoma at Washington University between March 2008 and September 2011 (group 1) were matched to 29 patients with identical nephrometry scores and comparable baseline renal function who underwent robot-assisted partial nephrectomy with hilar clamping during the same period (group 2). The matched cohorts' perioperative and renal functional outcomes were compared at a mean 9-month follow-up. Mean estimated blood loss was 146.4 mL in group 1, versus 103.9 mL in group 2 (P = .039). Mean hilar clamp time was 0 minutes in group 1 and 14.7 minutes in group 2. No perioperative complications were encountered in group 1; 1 Clavien-2 complication (3.4%) occurred in group 2 (P = 1.000). At 9-month follow-up, mean estimated glomerular filtration rate in group 1 was 79.9 versus 84.8 mL/min/1.73 m(2) preoperatively (P = .013); mean estimated glomerular filtration rate in group 2 was 74.1 versus 85.8 mL/min/1.73 m(2) preoperatively (P < .001). Hence, estimated glomerular filtration rate declined by a mean of 4.9 mL/min/1.73 m(2) in group 1 versus 11.7 mL/min/1.73 m(2) in group 2 (P = .033). Off-clamp robot-assisted partial nephrectomy is associated with a favorable morbidity profile and relatively greater renal functional preservation compared to clamped robot-assisted partial nephrectomy. Nevertheless, the benefit is small in renal functional terms and may have very limited clinical relevance. Copyright © 2012 Elsevier Inc. All rights reserved.

Timing embryo biopsy for PGD - before or after cryopreservation?

PubMed

Shinar, S; Kornecki, N; Schwartz, T; Mey-Raz, N; Amir, H; Almog, B; Shavit, T; Hasson, J

2016-09-01

Pre-implantation genetic diagnosis (PGD) is required in order to screen and diagnose embryos of patients at risk of having a genetically affected offspring. A biopsy to diagnose the genetic profile of the embryo may be performed either before or after cryopreservation. The aim of this study was to determine which biopsy timing yields higher embryo survival rates. Retrospective cohort study of all PGD patients in a public IVF unit between 2010 and 2013. Inclusion criteria were patients with good-quality embryos available for cryopreservation by the slow freezing method. Embryos were divided into two groups: biopsy before and biopsy after cryopreservation. The primary outcome was embryo survival rates post thawing. Sixty-five patients met inclusion criteria. 145 embryos were biopsied before cryopreservation and 228 embryos were cryopreserved and biopsied after thawing. Embryo survival was significantly greater in the latter group (77% vs. 68%, p < 0.0001). Cryopreservation preceding biopsy results in better embryo survival compared to biopsy before cryopreservation.

Effect of sterilization on stiffness and dimensional stability of rubber-dam clamps.

PubMed

Giebink, D L; Mathieu, G P; Hondrum, S O

1996-01-01

Simulated clinical conditions were used to test the effect of sterilization on rubber-dam clamp stiffness and dimension. Sixty Hygienic and Ivory W7 clamps were either steam or dry heat sterilized and compared to controls. Stiffness and dimensional change between Ivory clamp groups was significant (p<.0001); the sterilized clamps showed less change than the controls. Hygienic groups showed a significant different between the control and dry heat groups (p<.05); the sterilized clamps showed less change than the controls. The change in stiffness and interjaw width for all Ivory clamps compared to all Hygienic clamps was significant (p<.0001). The Hygienic clamps changes less than the Ivory clamps. The results indicate that steam and dry heat sterilization do not affect retention of rubber-dam clamps.

Comparison of efficacy, safety, and cost-effectiveness of in-office cup forcep biopsies versus operating room biopsies for laryngopharyngeal tumors.

PubMed

Naidu, Harini; Noordzij, J Pieter; Samim, Arang; Jalisi, Scharukh; Grillone, Gregory A

2012-09-01

To compare the diagnostic yield, safety, and cost of biopsies of laryngopharyngeal tumor performed in an office setting with those performed in the operating room (OR) under general anesthesia. This was a retrospective review of patients' records at Boston Medical Center from 2006 to 2008. In-office biopsies were performed using flexible digital videolaryngoscopy with cup forcep biopsies taken via the working channel in patients in whom cancer was strongly suspected. Patients whose in-office biopsies were nondiagnostic or suspected to be falsely negative were taken to the OR for biopsy under general anesthesia and served as the control group. Twelve patients fit the selection criteria and had in-office biopsies attempted. One patient could not tolerate the in-office biopsy. Seven of the 11 in-office biopsies performed were diagnostic for squamous cell carcinoma. The average cost (facility and professional otolaryngology charges) for an in-office biopsy was $2053.91. Five of these patients required further biopsy in the OR at an average cost (charges for surgeon, OR, anesthesia, and recovery room) of $9024.47. There were no significant complications reported for any of the procedures. In patients with strongly suspected laryngopharyngeal cancer, in-office cup forcep biopsies were 64% diagnostic. When compared with the OR, in-office cup biopsies of laryngopharyngeal tumor are safe and considerably more cost-effective. Although 36% of patients required operative biopsies, the cost would have been considerably higher in this cohort if all patients had gone to the OR for biopsies. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Biochemical artifacts in experiments involving repeated biopsies in the same muscle

PubMed Central

Van Thienen, Ruud; D'Hulst, Gommaar; Deldicque, Louise; Hespel, Peter

2014-01-01

Abstract Needle biopsies are being extensively used in clinical trials addressing muscular adaptation to exercise and diet. Still, the potential artifacts due to biopsy sampling are often overlooked. Healthy volunteers (n = 9) underwent two biopsies through a single skin incision in a pretest. Two days later (posttest) another biopsy was taken 3 cm proximally and 3 cm distally to the pretest incision. Muscle oxygenation status (tissue oxygenation index [TOI]) was measured by near‐infrared spectroscopy. Biopsy samples were analyzed for 40 key markers (mRNA and protein contents) of myocellular O2 sensing, inflammation, cell proliferation, mitochondrial biogenesis, protein synthesis and breakdown, oxidative stress, and energy metabolism. In the pretest, all measurements were identical between proximal and distal biopsies. However, compared with the pretest, TOI in the posttest was reduced in the proximal (−10%, P < 0.05), but not in the distal area. Conversely, most inflammatory markers were upregulated at the distal (100–500%, P < 0.05), but not at the proximal site. Overall, 29 of the 40 markers measured, equally distributed over all pathways studied, were either up‐ or downregulated by 50–500% (P < 0.05). In addition, 19 markers yielded conflicting results between the proximal and distal measurements (P < 0.05). This study clearly documents that prior muscle biopsies can cause major disturbances in myocellular signaling pathways in needle biopsies specimens sampled 48 h later. In addition, different biopsy sites within identical experimental conditions yielded conflicting results. PMID:24819751

Biochemical artifacts in experiments involving repeated biopsies in the same muscle.

PubMed

Van Thienen, Ruud; D'Hulst, Gommaar; Deldicque, Louise; Hespel, Peter

2014-01-01

Needle biopsies are being extensively used in clinical trials addressing muscular adaptation to exercise and diet. Still, the potential artifacts due to biopsy sampling are often overlooked. Healthy volunteers (n = 9) underwent two biopsies through a single skin incision in a pretest. Two days later (posttest) another biopsy was taken 3 cm proximally and 3 cm distally to the pretest incision. Muscle oxygenation status (tissue oxygenation index [TOI]) was measured by near-infrared spectroscopy. Biopsy samples were analyzed for 40 key markers (mRNA and protein contents) of myocellular O2 sensing, inflammation, cell proliferation, mitochondrial biogenesis, protein synthesis and breakdown, oxidative stress, and energy metabolism. In the pretest, all measurements were identical between proximal and distal biopsies. However, compared with the pretest, TOI in the posttest was reduced in the proximal (-10%, P < 0.05), but not in the distal area. Conversely, most inflammatory markers were upregulated at the distal (100-500%, P < 0.05), but not at the proximal site. Overall, 29 of the 40 markers measured, equally distributed over all pathways studied, were either up- or downregulated by 50-500% (P < 0.05). In addition, 19 markers yielded conflicting results between the proximal and distal measurements (P < 0.05). This study clearly documents that prior muscle biopsies can cause major disturbances in myocellular signaling pathways in needle biopsies specimens sampled 48 h later. In addition, different biopsy sites within identical experimental conditions yielded conflicting results.

Ultrasound-Guided Transcutaneous Needle Biopsy of the Base of the Tongue and Floor of the Mouth From a Submental Approach.

PubMed

Wagner, Jason M; Conrad, Rachel D; Cannon, Trinitia Y; Alleman, Anthony M

2016-05-01

Limited data exist regarding the feasibility of ultrasound-guided transcutaneous biopsy of the base of the tongue and floor of the mouth. This retrospective study reviewed 8 cases with lesions in the base of the tongue or floor of the mouth that were biopsied by fine-needle aspiration. Core biopsy was also needed in 1 case. All biopsies were technically successful, and all yielded squamous cell carcinoma. One biopsy yielded a false-positive result, as subsequent resection yielded high-grade dysplasia with no invasion. The other biopsy results were considered true-positive based on subsequent pathologic examinations (2 cases) or clinical/imaging follow-up (5 cases). There were no significant complications associated with the biopsies. © 2016 by the American Institute of Ultrasound in Medicine.

Trans-rectal interventional MRI: initial prostate biopsy experience

NASA Astrophysics Data System (ADS)

Greenwood, Bernadette M.; Behluli, Meliha R.; Feller, John F.; May, Stuart T.; Princenthal, Robert; Winkel, Alex; Kaminsky, David B.

2010-02-01

Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) of the prostate gland when evaluated along with T2-weighted images, diffusion-weighted images (DWI) and their corresponding apparent diffusion coefficient (ADC) maps can yield valuable information in patients with rising or elevated serum prostate-specific antigen (PSA) levels1. In some cases, patients present with multiple negative trans-rectal ultrasound (TRUS) biopsies, often placing the patient into a cycle of active surveillance. Recently, more patients are undergoing TRIM for targeted biopsy of suspicious findings with a cancer yield of ~59% compared to 15% for second TRUS biopsy2 to solve this diagnostic dilemma and plan treatment. Patients were imaged in two separate sessions on a 1.5T magnet using a cardiac phased array parallel imaging coil. Automated CAD software was used to identify areas of wash-out. If a suspicious finding was identified on all sequences it was followed by a second imaging session. Under MRI-guidance, cores were acquired from each target region3. In one case the microscopic diagnosis was prostatic intraepithelial neoplasia (PIN), in the other it was invasive adenocarcinoma. Patient 1 had two negative TRUS biopsies and a PSA level of 9ng/mL. Patient 2 had a PSA of 7.2ng/mL. He underwent TRUS biopsy which was negative for malignancy. He was able to go on to treatment for his prostate carcinoma (PCa)4. MRI may have an important role in a subset of patients with multiple negative TRUS biopsies and elevated or rising PSA.

Force-controlled patch clamp of beating cardiac cells.

PubMed

Ossola, Dario; Amarouch, Mohamed-Yassine; Behr, Pascal; Vörös, János; Abriel, Hugues; Zambelli, Tomaso

2015-03-11

From its invention in the 1970s, the patch clamp technique is the gold standard in electrophysiology research and drug screening because it is the only tool enabling accurate investigation of voltage-gated ion channels, which are responsible for action potentials. Because of its key role in drug screening, innovation efforts are being made to reduce its complexity toward more automated systems. While some of these new approaches are being adopted in pharmaceutical companies, conventional patch-clamp remains unmatched in fundamental research due to its versatility. Here, we merged the patch clamp and atomic force microscope (AFM) techniques, thus equipping the patch-clamp with the sensitive AFM force control. This was possible using the FluidFM, a force-controlled nanopipette based on microchanneled AFM cantilevers. First, the compatibility of the system with patch-clamp electronics and its ability to record the activity of voltage-gated ion channels in whole-cell configuration was demonstrated with sodium (NaV1.5) channels. Second, we showed the feasibility of simultaneous recording of membrane current and force development during contraction of isolated cardiomyocytes. Force feedback allowed for a gentle and stable contact between AFM tip and cell membrane enabling serial patch clamping and injection without apparent cell damage.

[Comparison of hot versus cold biopsy forceps in the diagnosis of endobronchial lesions].

PubMed

Firoozbakhsh, Shahram; Seifirad, Soroush; Safavi, Enayat; Dinparast, Reza; Taslimi, Shervin; Derakhshandeilami, Gholamreza

2011-11-01

Traditionally cold biopsy forceps were used for endobronchial biopsy, and recently electrocautery (hot) bronchoscopy biopsy forceps are introduced. It is hypothesized that hot biopsy forceps may decrease procedure related bleeding and also may decrease the quality of obtained samples. Patients with different indications for endobronchial biopsy during fiberoptic bronchoscopy underwent three hot and three cold biopsies with a random fashion. All biopsies were obtained with a single biopsy forceps with and without the application of an electrocoagulation current, set on soft coagulation mode (40W). A four point scale was used for quantification of bleeding. A single pathologist blinded to the patients' history was requested to review all samples. A three point scale was used to assess electrocoagulation damage. A total of 240 biopsies were obtained from 40 patients. Frequency of positive concordance between the two methods was 85%. The degree of electrocoagulation damage of the samples was as follows: grade 1=52.5%, grade 2=32.5%, and grade 3=15%. The average bleeding score following hot biopsy was significantly lower compared to the cold biopsy (P=.006). The concordance between diagnostic yield of hot and cold biopsies was 85%. There was no significant difference between the diagnostic yields of two biopsy methods (P=.687). Hot biopsy forceps significantly decreased the procedure related bleeding. The quality of samples was not impaired significantly. Regarding low prevalence of bleeding following endobronchial biopsy, routine use of hot bronchoscopy forceps is not reasonable. However, familiarity of bronchoscopists with this method may improve bronchoscopy safety. Copyright © 2011 SEPAR. Published by Elsevier Espana. All rights reserved.

EUS-guided biopsy for the diagnosis and classification of lymphoma.

PubMed

Ribeiro, Afonso; Pereira, Denise; Escalón, Maricer P; Goodman, Mark; Byrne, Gerald E

2010-04-01

EUS-guided FNA and Tru-cut biopsy (TCB) is highly accurate in the diagnosis of lymphoma. Subclassification, however, may be difficult in low-grade non-Hodgkin lymphoma and Hodgkin lymphoma. To determine the yield of EUS-guided biopsy to classify lymphoma based on the World Health Organization classification of tumors of hematopoietic lymphoid tissues. Retrospective study. Tertiary referral center. A total of 24 patients referred for EUS-guided biopsy who had a final diagnosis of lymphoma or "highly suspicious for lymphoma." EUS-guided FNA and TCB combined with flow cytometry (FC) analysis. MAIN OUTCOMES MEASUREMENT: Lymphoma subclassification accuracy of EUS guided biopsy. Twenty-four patients were included in this study. Twenty-three patients underwent EUS-FNA, and 1 patient had only TCB. Twenty-two underwent EUS-TCB combined with FNA. EUS correctly diagnosed lymphoma in 19 out of 24 patients (79%), and subclassification was determined in 16 patients (66.6%). Flow cytometry correctly identified B-cell monoclonality in 95% (18 out of 19). In 1 patient diagnosed as having marginal-zone lymphoma by EUS-FNA/FC only, the diagnosis was changed to hairy cell leukemia after a bone marrow biopsy was obtained. EUS had a lower yield in nonlarge B-cell lymphoma (only 9 out of 15 cases [60%]) compared with large B-cell lymphoma (78%; P = .3 [Fisher exact test]). Retrospective, small number of patients. EUS-guided biopsy has a lower yield to correctly classify Hodgkin lymphoma and low-grade lymphoma compared with high-grade diffuse large B-cell lymphoma. Copyright 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Piezoresistive cantilever force-clamp system

PubMed Central

Park, Sung-Jin; Petzold, Bryan C.; Goodman, Miriam B.; Pruitt, Beth L.

2011-01-01

We present a microelectromechanical device-based tool, namely, a force-clamp system that sets or “clamps” the scaled force and can apply designed loading profiles (e.g., constant, sinusoidal) of a desired magnitude. The system implements a piezoresistive cantilever as a force sensor and the built-in capacitive sensor of a piezoelectric actuator as a displacement sensor, such that sample indentation depth can be directly calculated from the force and displacement signals. A programmable real-time controller operating at 100 kHz feedback calculates the driving voltage of the actuator. The system has two distinct modes: a force-clamp mode that controls the force applied to a sample and a displacement-clamp mode that controls the moving distance of the actuator. We demonstrate that the system has a large dynamic range (sub-nN up to tens of μN force and nm up to tens of μm displacement) in both air and water, and excellent dynamic response (fast response time, <2 ms and large bandwidth, 1 Hz up to 1 kHz). In addition, the system has been specifically designed to be integrated with other instruments such as a microscope with patch-clamp electronics. We demonstrate the capabilities of the system by using it to calibrate the stiffness and sensitivity of an electrostatic actuator and to measure the mechanics of a living, freely moving Caenorhabditis elegans nematode. PMID:21529009

High throughput ion-channel pharmacology: planar-array-based voltage clamp.

PubMed

Kiss, Laszlo; Bennett, Paul B; Uebele, Victor N; Koblan, Kenneth S; Kane, Stefanie A; Neagle, Brad; Schroeder, Kirk

2003-02-01

Technological advances often drive major breakthroughs in biology. Examples include PCR, automated DNA sequencing, confocal/single photon microscopy, AFM, and voltage/patch-clamp methods. The patch-clamp method, first described nearly 30 years ago, was a major technical achievement that permitted voltage-clamp analysis (membrane potential control) of ion channels in most cells and revealed a role for channels in unimagined areas. Because of the high information content, voltage clamp is the best way to study ion-channel function; however, throughput is too low for drug screening. Here we describe a novel breakthrough planar-array-based HT patch-clamp technology developed by Essen Instruments capable of voltage-clamping thousands of cells per day. This technology provides greater than two orders of magnitude increase in throughput compared with the traditional voltage-clamp techniques. We have applied this method to study the hERG K(+) channel and to determine the pharmacological profile of QT prolonging drugs.

Post-therapy lesions in patients with non-Hodgkin's lymphoma characterized by 18F-FDG PET/CT-guided biopsy using automated robotic biopsy arm.

PubMed

Radhakrishnan, Renjith K; Mittal, Bhagwant R; Basher, Rajender K; Prakash, Gaurav; Malhotra, Pankaj; Kalra, Naveen; Das, Ashim

2018-01-01

The aim of this study was to analyse the positive predictive value (PPV) of post-therapy fluorine-18-fluorodeoxyglucose (F-FDG) PET/CT performed for response or recurrence evaluation in patients with non-Hodgkin's lymphoma (NHL) and to appraise the diagnostic utility of F-FDG PET/CT-guided biopsy in this setting. A total of 17 patients with NHL showing F-FDG avid lesions in F-FDG PET/CT performed for response or recurrence assessment underwent F-FDG PET/CT-guided biopsy using automated robotic biopsy arm needle navigation technique. The objectives were analysed in reference to histopathology. In all, 15 of the 17 (88.5%) procedures yielded adequate representative tissue samples. Nine out of 15 lesions were positive for residual disease and the remaining revealed benign findings on histopathology. One patient with inconclusive biopsy underwent surgical resection and histopathology confirmed the presence of residual disease. PPV of theF-FDG PET/CT was observed to be 62.5% (10/16). F-FDG PET/CT for response evaluation in NHL possesses a low PPV and hence warrants histopathological correlation when F-FDG PET/CT findings influence management decision. Diagnostic yield of F-FDG PET/CT-guided biopsy is high and has the potential to reduce sampling errors.

Value of percutaneous needle biopsy of small renal tumors in patients referred for cryoablation.

PubMed

Iguchi, Toshihiro; Hiraki, Takao; Gobara, Hideo; Fujiwara, Hiroyasu; Sakurai, Jun; Matsui, Yusuke; Araki, Motoo; Nasu, Yasutomo; Kanazawa, Susumu

2017-04-01

To retrospectively evaluate the safety and diagnostic yield of needle biopsy of small renal tumors, and the clinical consequences of performing needle biopsy in patients referred for percutaneous cryoablation before their treatment. Biopsy was performed for 120 tumors (mean diameter, 2.2 cm) in 119 patients. All procedures were divided into diagnostic and non-diagnostic biopsies. Various variables were compared between the two groups. All cryoablation procedures were divided into two groups: procedures with or without simultaneous biopsy. The rates of benign or non-diagnostic tumors in each group were compared. After performing 120 initial and eight repeat biopsies, Grade 1 bleedings occurred in 44 cases. Six tumors were non-diagnostic and 114 were pathologically diagnosed. There were no significant variables between the diagnostic and non-diagnostic biopsies. Unnecessary cryoablation was avoided in nine benign lesions by performing biopsy in advance. Cryoablation performed simultaneously with biopsy included significantly more benign or non-diagnostic tumors than cryoablation performed after biopsy (15.2% vs. 1.4%; p = .01). Percutaneous biopsy of small renal tumors referred for cryoablation was a safe procedure with high diagnostic yield. The confirmation of pathological diagnosis prior to cryoablation is necessary because patients with benign tumors can avoid unnecessary treatment.

Feasibility of re-biopsy and EGFR mutation analysis in patients with non-small cell lung cancer.

PubMed

Kim, Tae-Ok; Oh, In-Jae; Kho, Bo Gun; Park, Ha Young; Chang, Jin Sun; Park, Cheol-Kyu; Shin, Hong-Joon; Lim, Jung-Hwan; Kwon, Yong-Soo; Kim, Yu-Il; Lim, Sung-Chul; Kim, Young-Chul; Choi, Yoo-Duk

2018-05-14

In cases of EGFR-tyrosine kinase inhibitor (TKI) failure, re-biopsy may be useful to understand resistance mechanisms and guide further treatment decisions. However, performing re-biopsy is challenging because of several hurdles. We assessed the feasibility of re-biopsy in advanced non-small cell lung cancer (NSCLC) patients in real-world clinical practice. We retrospectively reviewed the clinical and pathologic data of advanced NSCLC patients who experienced disease progression after previous treatment with EGFR-TKIs at a single tertiary hospital in Korea between January 2014 and December 2016. Re-biopsy specimens included small biopsy, surgical tissue, or liquid-based cytology. EGFR mutation was tested using peptide nucleic acid-mediated clamping PCR. Of the 230 NSCLC patients that experienced progression after EGFR-TKI therapy, 105 (45.7%) underwent re-biopsy. Re-biopsy was successfully performed in 94 (89.5%) patients, and 11 patients were diagnosed with no malignancy. The complication rate was 8.6%, including seven cases of pneumothorax. EGFR mutation testing was performed on 75 patients using re-biopsy specimens. Of the 57 patients who had sensitizing mutations at diagnosis, T790M mutations were found in 19 (33.3%), while 38 (66.7%) had no T790M mutation. Multivariate analysis showed that the re-biopsy group was younger (P = 0.002) and exhibited a previous response to EGFR-TKIs (P < 0.001). Re-biopsy in advanced NSCLC is feasible in real world clinical practice, particularly in younger patients and those who achieved a previous response to EGFR-TKIs. © 2018 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Lotus birth, a holistic approach on physiological cord clamping.

PubMed

Zinsser, Laura A

2018-04-01

The positive effects of delayed cord clamping (DCC) has been extensively researched. DCC means: waiting at least one minute after birth before clamping and cutting the cord or till the pulsation has stopped. With physiological clamping and cutting (PCC) the clamping and cutting can happen at the earliest after the pulsation has stopped. With a Lotus birth, no clamping and cutting of the cord is done. A woman called Clair Lotus Day imitated the holistic approach of PCC from an anthropoid ape in 1974. The chimpanzee did not separate the placenta from the newborn. The aim of this case report is to discuss and learn a different approach in the third stage of labour. Three cases of Lotus birth by human beings were observed. All three women gave birth in an out-of-hospital setting and had ambulant postnatal care. The placenta was washed, salted and herbs were put on 2-3h post partum. The placenta was wrapped in something that absorbs the moisture. The salting was repeated with a degreasing frequency depending on moistness of the placenta. On life day six all three Lotus babies experiences a natural separation of the cord. All three Lotus birth cases were unproblematic, no special incidence occurred. One should differentiate between early cord clamping (ECC), delayed cord clamping (DCC) and physiological cord clamping (PCC). Lotus birth might lead to an optimisation of the bonding and attachment. Research is needed in the areas of both PCC and Lotus birth. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

Surface characterization of selected LDEF tray clamps

NASA Technical Reports Server (NTRS)

Cromer, T. F.; Grammer, H. L.; Wightman, J. P.; Young, Philip R.; Slemp, Wayne S.

1993-01-01

The surface characterization of chromic acid anodized 6061-T6 aluminum alloy tray clamps has shown differences in surface chemistry depending upon the position on the Long Duration Exposure Facility (LDEF). Water contact angle results showed no changes in wettability of the tray clamps. The overall surface topography of the control, trailing edge(E3) and leading edge(D9) samples was similar. The thickness of the aluminum oxide layer for all samples determined by Auger depth profiling was less than one micron. X-ray photoelectron spectroscopy (XPS) analysis of the tray clamps showed significant differences in the surface composition. Carbon and silicon containing compounds were the primary contaminants detected.

π-Clamp-mediated cysteine conjugation

NASA Astrophysics Data System (ADS)

Zhang, Chi; Welborn, Matthew; Zhu, Tianyu; Yang, Nicole J.; Santos, Michael S.; van Voorhis, Troy; Pentelute, Bradley L.

2016-02-01

Site-selective functionalization of complex molecules is one of the most significant challenges in chemistry. Typically, protecting groups or catalysts must be used to enable the selective modification of one site among many that are similarly reactive, and general strategies that selectively tune the local chemical environment around a target site are rare. Here, we show a four-amino-acid sequence (Phe-Cys-Pro-Phe), which we call the ‘π-clamp’, that tunes the reactivity of its cysteine thiol for site-selective conjugation with perfluoroaromatic reagents. We use the π-clamp to selectively modify one cysteine site in proteins containing multiple endogenous cysteine residues. These examples include antibodies and cysteine-based enzymes that would be difficult to modify selectively using standard cysteine-based methods. Antibodies modified using the π-clamp retained binding affinity to their targets, enabling the synthesis of site-specific antibody-drug conjugates for selective killing of HER2-positive breast cancer cells. The π-clamp is an unexpected approach to mediate site-selective chemistry and provides new avenues to modify biomolecules for research and therapeutics.

Comparison of Transjugular Liver Biopsy and Percutaneous Liver Biopsy With Tract Embolization in Pediatric Patients.

PubMed

Tulin-Silver, Sheryl; Obi, Chrystal; Kothary, Nishita; Lungren, Matthew

2018-03-05

The aim of the study was to compare safety and efficacy of transjugular liver biopsy (TJLB) and percutaneous liver biopsy (PLB) with tract embolization in pediatric patients with liver disease. TJLB and PLB between December 2009 and October 2015 were retrospectively reviewed. Primary endpoints were adequate sampling and complication rate. Patient age, weight, coagulation factors, ascites, blood transfusions, adequacy of biopsy sample, number of biopsy samples, and complications were compared. There were 39 TJLB (average age 10.6 years) and 120 PLB (average age 7.1 years) (P value <0.05). Average weight was 40.2 kg for TJLB and 26.8 kg for PLB (P value <0.05). Average platelets were 155 for TJLB and 252 for PLB (P value <0.05). Average INR was 1.7 for TJLB and 1.3 for PLB (P value <0.05). Mean postbiopsy hematocrit decrease was 0.8 and 0.9, for TJLB and PLB, respectively. Mean postbiopsy hemoglobin decrease was 0.3 in both groups. Number of core biopsy samples was 4.5 and 4.3, for TJLB and PLB, respectively. There was 1 biopsy yielding insufficient sample in each group. TJLB had 1 (2.6%) complication of supraventricular tachycardia. PLB had 4 (3.3%) complications, with 1 hemoperitoneum, 1 hypotension, 1 patient with decreased hemoglobin, and 1 patient with bilious drainage from the biopsy site. TJLB and PLB with gelatin sponge pledget tract embolization are both safe and effective for the diagnosis of hepatic disease in pediatric patients. To avoid radiation, PLB may be considered as first-line approach in the pediatric population, even in the setting of coagulopathy.

Added value of second biopsy target in screen-detected widespread suspicious breast calcifications.

PubMed

Falkner, Nathalie M; Hince, Dana; Porter, Gareth; Dessauvagie, Ben; Jeganathan, Sanjay; Bulsara, Max; Lo, Glen

2018-06-01

There is controversy on the optimal work-up of screen-detected widespread breast calcifications: whether to biopsy a single target or multiple targets. This study evaluates agreement between multiple biopsy targets within the same screen-detected widespread (≥25 mm) breast calcification to determine if the second biopsy adds value. Retrospective observational study of women screened in a statewide general population risk breast cancer mammographic screening program from 2009 to 2016. Screening episodes recalled for widespread calcifications where further views indicated biopsy, and two or more separate target areas were sampled within the same lesion were included. Percentage agreement and Cohen's Kappa were calculated. A total of 293317 women were screened during 761124 separate episodes with recalls for widespread calcifications in 2355 episodes. In 171 women, a second target was biopsied within the same lesion. In 149 (86%) cases, the second target biopsy result agreed with the first biopsy (κ = 0.6768). Agreement increased with increasing mammography score (85%, 86% and 92% for score 3, 4 and 5 lesions). Same day multiple biopsied lesions were three times more likely to yield concordant results compared to post-hoc second target biopsy cases. While a single target biopsy is sufficient to discriminate a benign vs. malignant diagnosis in most cases, in 14% there is added value in performing a second target biopsy. Biopsies performed prospectively are more likely to yield concordant results compared to post-hoc second target biopsy cases, suggesting a single prospective biopsy may be sufficient when results are radiological-pathological concordant; discordance still requires repeat sampling. © 2018 The Royal Australian and New Zealand College of Radiologists.

Zero-Time Renal Transplant Biopsies: A Comprehensive Review.

PubMed

Naesens, Maarten

2016-07-01

Zero-time kidney biopsies, obtained at time of transplantation, are performed in many transplant centers worldwide. Decisions on kidney discard, kidney allocation, and choice of peritransplant and posttransplant treatment are sometimes based on the histological information obtained from these biopsies. This comprehensive review evaluates the practical considerations of performing zero-time biopsies, the predictive performance of zero-time histology and composite histological scores, and the clinical utility of these biopsies. The predictive performance of individual histological lesions and of composite scores for posttransplant outcome is at best moderate. No single histological lesion or composite score is sufficiently robust to be included in algorithms for kidney discard. Dual kidney transplantation has been based on histological assessment of zero-time biopsies and improves outcome in individual patients, but the waitlist effects of this strategy remain obscure. Zero-time biopsies are valuable for clinical and translational research purposes, providing insight in risk factors for posttransplant events, and as baseline for comparison with posttransplant histology. The molecular phenotype of zero-time biopsies yields novel therapeutic targets for improvement of donor selection, peritransplant management and kidney preservation. It remains however highly unclear whether the molecular expression variation in zero-time biopsies could become a better predictor for posttransplant outcome than donor/recipient baseline demographic factors.

Spectral infrared hemispherical reflectance measurements for LDEF tray clamps

NASA Technical Reports Server (NTRS)

Cromwell, B. K.; Shepherd, S. D.; Pender, C. W.; Wood, B. E.

1993-01-01

Infrared hemispherical reflectance measurements that were made on 58 chromic acid anodized tray clamps from LDEF are described. The measurements were made using a hemiellipsoidal mirror reflectometer with interferometer for wavelengths between 2-15 microns. The tray clamps investigated were from locations about the entire spacecraft and provided the opportunity for comparing the effects of atomic oxygen at each location. Results indicate there was essentially no dependence on atomic oxygen fluence for the surfaces studied, but there did appear to be a slight dependence on solar radiation exposure. The reflectances of the front sides of the tray clamps consistently were slightly higher than for the protected rear tray clamp surfaces.

CT fluoroscopy-guided core needle biopsy of anterior mediastinal masses.

PubMed

Iguchi, T; Hiraki, T; Matsui, Y; Fujiwara, H; Sakurai, J; Masaoka, Y; Uka, M; Tanaka, T; Gobara, H; Kanazawa, S

2018-02-01

To retrospectively evaluate the safety, diagnostic yield, and risk factors of diagnostic failure of computed tomography (CT) fluoroscopy-guided biopsies of anterior mediastinal masses. Biopsy procedures and results of anterior mediastinal masses in 71 patients (32 women/39 men; mean [±standard deviation] age, 53.8±20.0years; range, 14-88years) were analyzed. Final diagnoses were based on surgical outcomes, imaging findings, or clinical follow-up findings. The biopsy results were compared with the final diagnosis, and the biopsy procedures grouped by pathologic findings into diagnostic success and failure groups. Multiple putative risk factors for diagnostic failure were then assessed. Seventy-one biopsies (71 masses; mean size, 67.5±27.3mm; range 8.6-128.2mm) were analyzed. We identified 17 grade 1 and one grade 2 adverse events (25.4% overall) according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Sixty-nine biopsies (97.2%) provided samples fit for pathologic analysis. Diagnostic failure was found for eight (11.3%) masses; the 63 masses diagnosed successfully included thymic carcinoma (n=17), lung cancer (n=14), thymoma (n=12), malignant lymphoma (n=11), germ cell tumor (n=3), and others (n=6). Using a thinner needle (i.e., a 20-gauge needle) was the sole significant risk factor for diagnostic failure (P=0.039). CT fluoroscopy-guided biopsy of anterior mediastinal masses was safe and had a high diagnostic yield; however, using a thinner biopsy needle significantly increased the risk of a failed diagnosis. Copyright © 2017 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Thoracic ultrasound-assisted selection for pleural biopsy with Abrams needle.

PubMed

Botana-Rial, Maribel; Leiro-Fernández, Virginia; Represas-Represas, Cristina; González-Piñeiro, Ana; Tilve-Gómez, Amara; Fernández-Villar, Alberto

2013-11-01

Closed pleural biopsy (CPB) in patients with malignant pleural effusion is less sensitive than cytology. Ultrasound-assisted CPB allows biopsies to be performed in the lower thoracic parietal pleura, where secondary spread from pleural metastases is initially more likely to be found. We analyzed whether choosing the point of entry for CPB with thoracic ultrasound assistance influences the diagnostic yield in malignant pleural effusion. This prospective study included patients who underwent CPB performed by an experienced pulmonologist in 2008-2010 (group A) and thoracic ultrasound was used to select the biopsy site. The results were compared with a historical series of CPB performed by the same pulmonologist without the assistance of thoracic ultrasound (group B). An Abrams needle was used in all cases. We analyzed the obtaining of pleural tissue and the diagnostic yield. We included 114 CPBs from group A (23% tuberculous pleural effusion, 27% malignant pleural effusion) and 67 CPBs from group B (24% tuberculous pleural effusion, 30% malignant pleural effusion) (P = .70). Pleural tissue was obtained in 96.5% of the group A CPBs and 89.6% of the group B CPBs (P = .05). The diagnostic yields of CPB for tuberculous pleural effusion and malignant pleural effusion in group A were 89.5% and 77.4%, respectively, and 91.7% and 60%, respectively, in group B (P = .80 for tuberculous pleural effusion, and P = .18 for malignant pleural effusion). Selecting the point of entry for CPB using thoracic ultrasound increases the likelihood of obtaining pleural tissue and the diagnostic yield, but without statistical significance. We recommend ultrasound-assisted CPB to investigate pleural effusion, since the diagnostic yield of a pleural biopsy with an Abrams needle increased by > 17% in subjects with malignant pleural effusion.

Guided percutaneous fine-needle aspiration biopsy of the liver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ho, C.S.; McLoughlin, M.J.; Tao, L.C.

1981-04-01

Forty patients with suspected malignant disease of the liver underwent percutaneous fine-needle aspiration biopsy with radioisotope scintigraphic and fluoroscopic guidance. The needle was aimed at focal defects identified on the liver scan and several passes were made. When the scan was diffusely abnormal, the liver was widely sampled with multiple passes. Thirty patients were eventually considered to have malignant disease and aspiration biopsy was positive in 28 (93%) of these patients, including 25 of 26 with liver metastases (96%). There were two false-positive results and one minor complication. In 24 patients, conventional wide-bore needle biopsy was also performed. In thismore » group, 16 patients had a final diagnosis of hepatic malignancy. Aspiration biopsies were positive in 14 of these (87%) and conventional needle biopsies were positive in four (25%). Guided percutaneous fine-needle aspiration biopsy is recommended for pathologic diagnosis of hepatic malignancy because of its simplicity, high yield, and reasonable safety.« less

Planar patch clamp for neuronal networks--considerations and future perspectives.

PubMed

Bosca, Alessandro; Martina, Marzia; Py, Christophe

2014-01-01

The patch-clamp technique is generally accepted as the gold standard for studying ion channel activity allowing investigators to either "clamp" membrane voltage and directly measure transmembrane currents through ion channels, or to passively monitor spontaneously occurring intracellular voltage oscillations. However, this resulting high information content comes at a price. The technique is labor-intensive and requires highly trained personnel and expensive equipment. This seriously limits its application as an interrogation tool for drug development. Patch-clamp chips have been developed in the last decade to overcome the tedious manipulations associated with the use of glass pipettes in conventional patch-clamp experiments. In this chapter, we describe some of the main materials and fabrication protocols that have been developed to date for the production of patch-clamp chips. We also present the concept of a patch-clamp chip array providing high resolution patch-clamp recordings from individual cells at multiple sites in a network of communicating neurons. On this chip, the neurons are aligned with the aperture-probes using chemical patterning. In the discussion we review the potential use of this technology for pharmaceutical assays, neuronal physiology and synaptic plasticity studies.

Patch-Clamp Recording from Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes: Improving Action Potential Characteristics through Dynamic Clamp

PubMed Central

Veerman, Christiaan C.; Zegers, Jan G.; Mengarelli, Isabella; Bezzina, Connie R.

2017-01-01

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) hold great promise for studying inherited cardiac arrhythmias and developing drug therapies to treat such arrhythmias. Unfortunately, until now, action potential (AP) measurements in hiPSC-CMs have been hampered by the virtual absence of the inward rectifier potassium current (IK1) in hiPSC-CMs, resulting in spontaneous activity and altered function of various depolarising and repolarising membrane currents. We assessed whether AP measurements in “ventricular-like” and “atrial-like” hiPSC-CMs could be improved through a simple, highly reproducible dynamic clamp approach to provide these cells with a substantial IK1 (computed in real time according to the actual membrane potential and injected through the patch-clamp pipette). APs were measured at 1 Hz using perforated patch-clamp methodology, both in control cells and in cells treated with all-trans retinoic acid (RA) during the differentiation process to increase the number of cells with atrial-like APs. RA-treated hiPSC-CMs displayed shorter APs than control hiPSC-CMs and this phenotype became more prominent upon addition of synthetic IK1 through dynamic clamp. Furthermore, the variability of several AP parameters decreased upon IK1 injection. Computer simulations with models of ventricular-like and atrial-like hiPSC-CMs demonstrated the importance of selecting an appropriate synthetic IK1. In conclusion, the dynamic clamp-based approach of IK1 injection has broad applicability for detailed AP measurements in hiPSC-CMs. PMID:28867785

30 CFR 75.605 - Clamping of trailing cables to equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment. [Statutory Provisions] Trailing cables shall be clamped to...

An Ultrasonic Clamp for Bloodless Partial Nephrectomy

NASA Astrophysics Data System (ADS)

Lafon, Cyril; Bouchoux, Guillaume; Murat, François Joseph; Birer, Alain; Theillère, Yves; Chapelon, Jean Yves; Cathignol, Dominique

2007-05-01

Maximum conservation of the kidney is preferable through partial nephrectomy for patients at risk of disease recurrence of renal cancers. Haemostatic tools are needed in order to achieve bloodless surgery and reduce post surgery morbidity. Two piezo-ceramic transducers operating at a frequency of 4 MHz were mounted on each arm of a clamp. When used for coagulation purposes, two transducers situated on opposite arms of the clamp were driven simultaneously. Heat delivery was optimized as each transducers mirrored back to targeted tissues the wave generated by the opposite transducer. Real-time treatment monitoring with an echo-based technique was also envisaged with this clamp. Therapy was periodically interrupted so one transducer could generate a pulse. The echo returning from the opposite transducer was treated. Coagulation necroses were obtained in vitro on substantial thicknesses (23-38mm) of pig liver over exposure durations ranging from 30s to 130s, and with acoustic intensities of less than 15W/cm2 per transducer. Both kidneys of two pigs were treated in vivo with the clamp (14.5W/cm2 for 90s), and the partial nephrectomies performed proved to be bloodless. In vitro and in vivo, wide transfixing lesions corresponded to an echo energy decrease superior to -10dB and parabolic form of the time of flight versus treatment time. In conclusion, this ultrasound clamp has proven to be an excellent mean for achieving monitored haemostasis in kidney.

[Muscle biopsy in children: Usefulness in 2012].

PubMed

Cuisset, J-M; Maurage, C-A; Carpentier, A; Briand, G; Thévenon, A; Rouaix, N; Vallée, L

2013-01-01

Muscle biopsy is a mainstay diagnostic tool for investigating neuromuscular disorders in children. We report the yield of pediatric muscle biopsy in a population of 415 children by a retrospective study of 419 biopsies performed between 1/01/2000 and 31/12/2009 in a neuropediatric department, including mitochondrial respiratory chain analysis for 87 children. Two hundred and fifty-five biopsies were from boys (61%) 164 from girls (39%). Their mean age at biopsy was 6.5years; 155 (37%) biopsies were obtained before the child was 5years old. Final histopathological diagnoses were: congenital myopathy (n=193, including 15 structural congenital myopathies); progressive muscular dystrophy (n=75 [18%] including 57 dystrophinopathies); congenital muscular dystrophy (n=17, including six primary merosinopathies); dermatomyositis (n=11); spinal muscular atrophy (n=9, including six atypical spinal muscular atrophies); metabolic myopathy (n=32, including 19 mitochondrial myopathies); encephalomyopathy (n=53 [13%], including 27 with a mitochondrial respiratory chain defect). Pathological diagnosis remained undetermined in 16 cases. In 184 patients (44%), the muscle biopsy revealed specific histopathological anomalies (dystrophic process; specific ultrastructural abnormalities; perifascicular atrophy; neurogenic atrophy; metabolic anomalies) enabling a precise etiological diagnosis. For 85% of progressive muscular dystrophies, the biopsy resulted in a genetic diagnosis after identification of the protein defect. In 15% of the congenital myopathies, histopathological anomalies focused attention on one or several genes. Concerning dystrophinopathies, quantification of dystrophin deficiency on the biopsy specimen contributed to the definition of the clinical phenotype: Duchenne, or Becker. In children with a myopathy, muscle biopsy is often indispensable to establish the etiological diagnosis. Based on the results from this series, muscle biopsy can provide a precise

Carbon nanotube-clamped metal atomic chain

PubMed Central

Tang, Dai-Ming; Yin, Li-Chang; Li, Feng; Liu, Chang; Yu, Wan-Jing; Hou, Peng-Xiang; Wu, Bo; Lee, Young-Hee; Ma, Xiu-Liang; Cheng, Hui-Ming

2010-01-01

Metal atomic chain (MAC) is an ultimate one-dimensional structure with unique physical properties, such as quantized conductance, colossal magnetic anisotropy, and quantized magnetoresistance. Therefore, MACs show great potential as possible components of nanoscale electronic and spintronic devices. However, MACs are usually suspended between two macroscale metallic electrodes; hence obvious technical barriers exist in the interconnection and integration of MACs. Here we report a carbon nanotube (CNT)-clamped MAC, where CNTs play the roles of both nanoconnector and electrodes. This nanostructure is prepared by in situ machining a metal-filled CNT, including peeling off carbon shells by spatially and elementally selective electron beam irradiation and further elongating the exposed metal nanorod. The microstructure and formation process of this CNT-clamped MAC are explored by both transmission electron microscopy observations and theoretical simulations. First-principles calculations indicate that strong covalent bonds are formed between the CNT and MAC. The electrical transport property of the CNT-clamped MAC was experimentally measured, and quantized conductance was observed. PMID:20427743

Spectral infrared hemispherical reflectance measurements for LDEF tray clamps

NASA Technical Reports Server (NTRS)

Wood, Bobby E.; Cromwell, Brian K.; Pender, Charles W.; Shepherd, Seth D.

1992-01-01

This paper describes infrared hemispherical reflectance measurements (2-15 microns) that were made on 58 chromic acid anodized tray clamps retrieved from the LDEF spacecraft. These clamps were used for maintaining the experiments in place and were located at various locations about the spacecraft. Changes in reflectance of the tray clamps at these locations were compared with atomic oxygen fluxes at the same locations. A decrease in absorption band depth was seen for the surfaces exposed to space indicating that there was some surface layer erosion. In all of the surfaces measured, little evidence of contamination was observed and none of the samples showed evidence of the brown nicotine stain that was so prominent in other experiments. Total emissivity values were calculated for both exposed and unexposed tray clamp surfaces. Only small differences, usually less than 1 percent, were observed. The spectral reflectances were measured using a hemi-ellipsoidal mirror reflectometer matched with an interferometer spectrometer. The rapid scanning capability of the interferometer allowed the reflectance measurements to be made in a timely fashion. The ellipsoidal mirror has its two foci separated by 2 inches and located on the major axis. A blackbody source was located at one focus while the tray clamp samples were located at the conjugate focus. The blackbody radiation was modulated and then focused by the ellipsoid onto the tray clamps. Radiation reflected from the tray clamp was sampled by the interferometer by viewing through a hole in the ellipsoid. A gold mirror (reflectance approximately 98 percent) was used as the reference surface.

Tensil Film Clamps And Mounting Block For Viscoelastometers

NASA Technical Reports Server (NTRS)

Stoakley, Diane M.; St. Clair, Anne K.; Little, Bruce D.

1989-01-01

Set of clamps and mounting block developed for use in determining tensile moduli and damping properties of films in manually operated or automated commercial viscoelastometer. These clamps and block provide uniformity of sample gripping and alignment in instrument. Dependence on operator and variability of data greatly reduced.

Intrinsic Frequency and the Single Wave Biopsy

PubMed Central

Petrasek, Danny; Pahlevan, Niema M.; Tavallali, Peyman; Rinderknecht, Derek G.; Gharib, Morteza

2015-01-01

Insulin resistance is the hallmark of classical type II diabetes. In addition, insulin resistance plays a central role in metabolic syndrome, which astonishingly affects 1 out of 3 adults in North America. The insulin resistance state can precede the manifestation of diabetes and hypertension by years. Insulin resistance is correlated with a low-grade inflammatory condition, thought to be induced by obesity as well as other conditions. Currently, the methods to measure and monitor insulin resistance, such as the homeostatic model assessment and the euglycemic insulin clamp, can be impractical, expensive, and invasive. Abundant evidence exists that relates increased pulse pressure, pulse wave velocity (PWV), and vascular dysfunction with insulin resistance. We introduce a potential method of assessing insulin resistance that relies on a novel signal-processing algorithm, the intrinsic frequency method (IFM). The method requires a single pulse pressure wave, thus the term “ wave biopsy.” PMID:26183600

A monogenean without clamps

USDA-ARS?s Scientific Manuscript database

Ectoparasites face a daily challenge: to remain attached to their host. Polyopisthocotylean monogeneans attach to the surface of fish gills by highly specialized structures, the sclerotized clamps. In the original description of the protomicrocotylid species Lethacotyle fijiensis, described 50 years...

Dynamic analysis of clamp band joint system subjected to axial vibration

NASA Astrophysics Data System (ADS)

Qin, Z. Y.; Yan, S. Z.; Chu, F. L.

2010-10-01

Clamp band joints are commonly used for connecting circular components together in industry. Some of the systems jointed by clamp band are subjected to dynamic load. However, very little research on the dynamic characteristics for this kind of joint can be found in the literature. In this paper, a dynamic model for clamp band joint system is developed. Contact and frictional slip between the components are accommodated in this model. Nonlinear finite element analysis is conducted to identify the model parameters. Then static experiments are carried out on a scaled model of the clamp band joint to validate the joint model. Finally, the model is adopted to study the dynamic characteristics of the clamp band joint system subjected to axial harmonic excitation and the effects of the wedge angle of the clamp band joint and the preload on the response. The model proposed in this paper can represent the nonlinearity of the clamp band joint and be used conveniently to investigate the effects of the structural and loading parameters on the dynamic characteristics of this type of joint system.

Planar patch clamp: advances in electrophysiology.

PubMed

Brüggemann, Andrea; Farre, Cecilia; Haarmann, Claudia; Haythornthwaite, Ali; Kreir, Mohamed; Stoelzle, Sonja; George, Michael; Fertig, Niels

2008-01-01

Ion channels have gained increased interest as therapeutic targets over recent years, since a growing number of human and animal diseases have been attributed to defects in ion channel function. Potassium channels are the largest and most diverse family of ion channels. Pharmaceutical agents such as Glibenclamide, an inhibitor of K(ATP) channel activity which promotes insulin release, have been successfully sold on the market for many years. So far, only a small group of the known ion channels have been addressed as potential drug targets. The functional testing of drugs on these ion channels has always been the bottleneck in the development of these types of pharmaceutical compounds.New generations of automated patch clamp screening platforms allow a higher throughput for drug testing and widen this bottleneck. Due to their planar chip design not only is a higher throughput achieved, but new applications have also become possible. One of the advantages of planar patch clamp is the possibility of perfusing the intracellular side of the membrane during a patch clamp experiment in the whole-cell configuration. Furthermore, the extracellular membrane remains accessible for compound application during the experiment.Internal perfusion can be used not only for patch clamp experiments with cell membranes, but also for those with artificial lipid bilayers. In this chapter we describe how internal perfusion can be applied to potassium channels expressed in Jurkat cells, and to Gramicidin channels reconstituted in a lipid bilayer.

Rectal biopsy

MedlinePlus

... biopsy; Amyloidosis - rectal biopsy; Crohn disease - rectal biopsy; Colorectal cancer - biopsy; Hirschsprung disease - rectal biopsy ... abnormal conditions of the rectum, such as: Abscesses Colorectal ... Inflammation Tumors Amyloidosis Crohn disease Hirschsprung ...

A novel high performance ESD power clamp circuit with a small area

NASA Astrophysics Data System (ADS)

Zhaonian, Yang; Hongxia, Liu; Li, Li; Qingqing, Zhuo

2012-09-01

A MOSFET-based electrostatic discharge (ESD) power clamp circuit with only a 10 ns RC time constant for a 0.18-μm process is proposed. A diode-connected NMOSFET is used to maintain a long delay time and save area. The special structure overcomes other shortcomings in this clamp circuit. Under fast power-up events, the gate voltage of the clamp MOSFET does not rise as quickly as under ESD events, the special structure can keep the clamp MOSFET thoroughly off. Under a falsely triggered event, the special structure can turn off the clamp MOSFET in a short time. The clamp circuit can also reject the power supply noise effectively. Simulation results show that the clamp circuit avoids fast false triggering events such as a 30 ns/1.8 V power-up, maintains a 1.2 μs delay time and a 2.14 μs turn-off time, and reduces to about 70% of the RC time constant. It is believed that the proposed clamp circuit can be widely used in high-speed integrated circuits.

Bone Biopsy

MedlinePlus

... News Physician Resources Professions Site Index A-Z Bone Biopsy Bone biopsy uses a needle and imaging ... the limitations of Bone Biopsy? What is a Bone Biopsy? A bone biopsy is an image-guided ...

Needle Biopsy

MedlinePlus

... needle biopsy procedures include fine-needle aspiration and core needle biopsy. Needle biopsy may be used to ... hollow needle to draw cells from your body. Core needle biopsy. This type of needle biopsy uses ...

A structural and mechanistic study of π-clamp-mediated cysteine perfluoroarylation.

PubMed

Dai, Peng; Williams, Jonathan K; Zhang, Chi; Welborn, Matthew; Shepherd, James J; Zhu, Tianyu; Van Voorhis, Troy; Hong, Mei; Pentelute, Bradley L

2017-08-11

Natural enzymes use local environments to tune the reactivity of amino acid side chains. In searching for small peptides with similar properties, we discovered a four-residue π-clamp motif (Phe-Cys-Pro-Phe) for regio- and chemoselective arylation of cysteine in ribosomally produced proteins. Here we report mutational, computational, and structural findings directed toward elucidating the molecular factors that drive π-clamp-mediated arylation. We show the significance of a trans conformation prolyl amide bond for the π-clamp reactivity. The π-clamp cysteine arylation reaction enthalpy of activation (ΔH ‡ ) is significantly lower than a non-π-clamp cysteine. Solid-state NMR chemical shifts indicate the prolyl amide bond in the π-clamp motif adopts a 1:1 ratio of the cis and trans conformation, while in the reaction product Pro3 was exclusively in trans. In two structural models of the perfluoroarylated product, distinct interactions at 4.7 Å between Phe1 side chain and perfluoroaryl electrophile moiety are observed. Further, solution 19 F NMR and isothermal titration calorimetry measurements suggest interactions between hydrophobic side chains in a π-clamp mutant and the perfluoroaryl probe. These studies led us to design a π-clamp mutant with an 85-fold rate enhancement. These findings will guide us toward the discovery of small reactive peptides to facilitate abiotic chemistry in water.

Cone biopsy

MedlinePlus

... grade cone biopsy; High-grade cone biopsy; Carcinoma in situ-cone biopsy; CIS - cone biopsy; ASCUS - cone biopsy; ... marked dysplasia CIN III -- severe dysplasia to carcinoma in situ Abnormal results may also be due to cervical ...

Solutions for transients in arbitrarily branching cables: III. Voltage clamp problems.

PubMed

Major, G

1993-07-01

Branched cable voltage recording and voltage clamp analytical solutions derived in two previous papers are used to explore practical issues concerning voltage clamp. Single exponentials can be fitted reasonably well to the decay phase of clamped synaptic currents, although they contain many underlying components. The effective time constant depends on the fit interval. The smoothing effects on synaptic clamp currents of dendritic cables and series resistance are explored with a single cylinder + soma model, for inputs with different time courses. "Soma" and "cable" charging currents cannot be separated easily when the soma is much smaller than the dendrites. Subtractive soma capacitance compensation and series resistance compensation are discussed. In a hippocampal CA1 pyramidal neurone model, voltage control at most dendritic sites is extremely poor. Parameter dependencies are illustrated. The effects of series resistance compound those of dendritic cables and depend on the "effective capacitance" of the cell. Plausible combinations of parameters can cause order-of-magnitude distortions to clamp current waveform measures of simulated Schaeffer collateral inputs. These voltage clamp problems are unlikely to be solved by the use of switch clamp methods.

Clinical aspects of incorporating cord clamping into stabilisation of preterm infants.

PubMed

Knol, Ronny; Brouwer, Emma; Vernooij, Alex S N; Klumper, Frans J C M; DeKoninck, Philip; Hooper, Stuart B; Te Pas, Arjan B

2018-04-21

Fetal to neonatal transition is characterised by major pulmonary and haemodynamic changes occurring in a short period of time. In the international neonatal resuscitation guidelines, comprehensive recommendations are available on supporting pulmonary transition and delaying clamping of the cord in preterm infants. Recent experimental studies demonstrated that the pulmonary and haemodynamic transition are intimately linked, could influence each other and that the timing of umbilical cord clamping should be incorporated into the respiratory stabilisation. We reviewed the current knowledge on how to incorporate cord clamping into stabilisation of preterm infants and the physiological-based cord clamping (PBCC) approach, with the infant's transitional status as key determinant of timing of cord clamping. This approach could result in optimal timing of cord clamping and has the potential to reduce major morbidities and mortality in preterm infants. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Diffuse reflectance imaging: a tool for guided biopsy

NASA Astrophysics Data System (ADS)

Jayanthi, Jayaraj L.; Subhash, Narayanan; Manju, Stephen; Nisha, Unni G.; Beena, Valappil T.

2012-01-01

Accurate diagnosis of premalignant or malignant oral lesions depends on the quality of the biopsy, adequate clinical information and correct interpretation of the biopsy results. The major clinical challenge is to precisely locate the biopsy site in a clinically suspicious lesion. Dips due to oxygenated hemoglobin absorption have been noticed at 545 and 575 nm in the diffusely reflected white light spectra of oral mucosa and the intensity ratio R545/R575 has been found suited for early detection of oral pre-cancers. A multi-spectral diffuse reflectance (DR) imaging system has been developed consisting of an electron multiplying charge coupled device (EMCCD) camera and a liquid crystal tunable filter for guiding the clinician to an optimal biopsy site. Towards this DR images were recorded from 27 patients with potentially malignant lesions on their tongue (dorsal, lateral and ventral sides) and from 44 healthy controls at 545 and 575 nm with the DR imaging system. False colored ratio image R545/R575 of the lesion provides a visual discerning capability that helps in locating the most malignant site for biopsy. Histopathological report of guided biopsy showed that out of the 27 patients 16 were cancers, 9 pre-cancers and 2 lichen planus. In this clinical trial DR imaging has correctly guided 25 biopsy sites, yielding a sensitivity of 93% and a specificity of 98%, thereby establishing the potential of DR imaging as a tool for guided biopsy.

An ideal clamping analysis for a cross-ply laminate

NASA Technical Reports Server (NTRS)

Valisetty, R. R.; Murthy, P. L. N.; Rehfield, L. W.

1988-01-01

Different elementary clamping models are discussed for a three layer crossply laminate to study the sensitivity of clamping to the definition of cross-sectional rotation. All of these models leave a considerable residual warping at the edges. Using a complimentary energy principle and principle of superposition, an analysis is conducted to reduce this residual warping. This led to the identification of exact interior solution corresponding to the ideal clamping. This study also suggests a presence of stress singularities at the corners and between different layers near the fixed edge.

Analysis of "dry" mesothelioma with ultrasound guided biopsies.

PubMed

Stigt, Jos A; Boers, James E; Groen, Harry J M

2012-12-01

Image-guided sampling of the thickened pleura is a sensitive approach in patients with malignant pleural mesothelioma with pleural effusion. Malignant pleural mesothelioma presenting without effusion however is more of a diagnostic challenge. In this study we report the diagnostic yield and complications of ultrasound-guided cutting needle biopsies in this particular category of patients. A retrospective database analysis from September 2007 until January 2012 was performed in 56 patients with malignant pleural mesothelioma. Clinical characteristics and results of diagnostic evaluations were analysed. Of the 56 patients with malignant pleural mesothelioma, 20 patients presented without pleural effusion of with locular effusion. Ultrasound-guided cutting needle biopsy was performed in 14/20 patients with a diagnostic accuracy of 80%. Only 1 patient had mild haemoptysis immediately following biopsies. Diagnosing patients with pleural thickenings suspect for malignant mesothelioma without pleural effusion or with loculated pleural effusion is effective and safe with ultrasound-guided cutting needle biopsies. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Kidney Biopsy Adequacy: A Metric-based Study.

PubMed

Ferrer, German; Andeen, Nicole K; Lockridge, Joseph; Norman, Douglas; Foster, Bryan R; Houghton, Donald C; Troxell, Megan L

2018-06-05

There are differences in renal biopsy yield related to on-site evaluation, tissue division, and operator, among others. To understand these variations, we collected adequacy-associated data (%cortex, glomeruli, arteries, length) from consecutive native and allograft kidney biopsies over a 22-month period. In total, 1332 biopsies (native: 873, allograft: 459) were included, 617 obtained by nephrologists, 663 by radiologists, and 559 with access to on-site division. Proceduralists with access to on-site evaluation had significantly lower inadequacy rates and better division of tissue for light microscopy (LM), immunofluorescence, and electron microscopy than those without access to on-site evaluation. Radiologists in our region were significantly less likely to have access to on-site evaluation than nephrologists. On multivariate analysis for native kidney biopsies, the effect of having a radiologist perform the biopsy and having access to on-site division were both significant predictors of obtaining greater calculated amount of cortex for LM. Despite the trend for radiologists to obtain more tissue in general, biopsies from nephrologists contained a greater percentage of cortex and were more likely to be considered adequate for LM (native kidney inadequacy rate for LM: 1.11% vs. 5.41%, P=0.0086). Biopsies in which inadequate or marginal cortical tissue was submitted for LM had only minor decreases in the amount of cortex submitted for immunofluorescence and electron microscopy, revealing an opportunity for improved specimen triaging when limited tissue is obtained. In conclusion, both on-site evaluation/division and proceduralist significantly affect quantitative kidney biopsy metrics, which in turn affects the pathologist's ability to render an accurate diagnosis with appropriate prognostic information for the patient and treating nephrologist.

High-speed pressure clamp.

PubMed

Besch, Stephen R; Suchyna, Thomas; Sachs, Frederick

2002-10-01

We built a high-speed, pneumatic pressure clamp to stimulate patch-clamped membranes mechanically. The key control element is a newly designed differential valve that uses a single, nickel-plated piezoelectric bending element to control both pressure and vacuum. To minimize response time, the valve body was designed with minimum dead volume. The result is improved response time and stability with a threefold decrease in actuation latency. Tight valve clearances minimize the steady-state air flow, permitting us to use small resonant-piston pumps to supply pressure and vacuum. To protect the valve from water contamination in the event of a broken pipette, an optical sensor detects water entering the valve and increases pressure rapidly to clear the system. The open-loop time constant for pressure is 2.5 ms for a 100-mmHg step, and the closed-loop settling time is 500-600 micros. Valve actuation latency is 120 micros. The system performance is illustrated for mechanically induced changes in patch capacitance.

Bowel lesions: percutaneous US-guided 18-gauge needle biopsy--preliminary experience.

PubMed

Tudor, G R; Rodgers, P M; West, K P

1999-08-01

Ultrasonography-guided percutaneous biopsy was performed with local anesthesia and an 18-gauge needle in 10 patients with bowel-wall lesions. All patients underwent clinical review within 1 month. Biopsy was diagnostic in all patients. There were no complications, and all patients tolerated the procedure well. The technique appears to be safe and had an excellent diagnostic yield in our series.

Analysis of impactor residues in tray clamps from the Long Duration Exposure Facility. Part 2: Clamps from Bay B of the satellite

NASA Technical Reports Server (NTRS)

Bernhard, Ronald P.; Zolensky, Michael E.

1994-01-01

The Long Duration Exposure Facility (LDEF) was placed in low-Earth orbit (LEO) in 1984 and recovered 5.7 years later. The LDEF was host to several individual experiments specifically designed to characterize critical aspects of meteoroid and debris environment in LEO. However, it was realized from the beginning that the most efficient use of the satellite would be to examine the entire surface for impact features. In this regard, particular interest centered on common exposed materials that faced in all LDEF pointing directions. Among the most important of these materials was the tray clamps. Therefore, in an effort to better understand the nature of particulates in LEO and their effects on spacecraft hardware, residues found in impact features on LDEF tray clamp surfaces are being analyzed. This catalog presents all data from clamps from Bay B of the LDEF. NASA Technical Memorandum 104759 has cataloged impacts that occurred on Bay B (published March 1993). Subsequent catalogs will include clamps from succeeding bays of the satellite.

Single-Institution Results of Image-Guided Nonplugged Percutaneous Versus Transjugular Liver Biopsy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hardman, Rulon L., E-mail: hardmanr@uthscsa.edu; Perrich, Kiley D.; Silas, Anne M.

2011-04-15

Purpose: To retrospectively review patients who underwent transjugular and image-guided percutaneous biopsy and compare the relative risk of ascites, thrombocytopenia, and coagulopathy. Materials and Methods: From August 2001 through February 2006, a total of 238 liver biopsies were performed. The radiologist reviewed all patient referrals for transjugular biopsy. These patients either underwent transjugular biopsy or were reassigned to percutaneous biopsy (crossover group). Patients referred to percutaneous image-guided liver biopsy underwent this same procedure. Biopsies were considered successful if a tissue diagnosis could be made from the samples obtained. Results: A total of 36 transjugular biopsies were performed with 3 totalmore » (8.3%) and 1 major (2.8%) complications. A total of 171 percutaneous biopsies were performed with 10 (5.8%) total and 3 (1.8%) major complications. The crossover group showed a total of 4 (12.9%) complications with 1 (3.2%) major complication. Sample adequacy was 91.9% for transjugular and 99.5% for percutaneous biopsy. Conclusion: Both transjugular and percutaneous liver biopsy techniques are efficacious and safe. Contraindications such as thrombocytopenia, coagulopathy, and ascites are indicators of greater complications but are not necessarily prevented by transjugular biopsy. Percutaneous biopsy more frequently yields a diagnostic specimen than transjugular biopsy.« less

Dynamic Clamp in Cardiac and Neuronal Systems Using RTXI

PubMed Central

Ortega, Francis A.; Butera, Robert J.; Christini, David J.; White, John A.; Dorval, Alan D.

2016-01-01

The injection of computer-simulated conductances through the dynamic clamp technique has allowed researchers to probe the intercellular and intracellular dynamics of cardiac and neuronal systems with great precision. By coupling computational models to biological systems, dynamic clamp has become a proven tool in electrophysiology with many applications, such as generating hybrid networks in neurons or simulating channelopathies in cardiomyocytes. While its applications are broad, the approach is straightforward: synthesizing traditional patch clamp, computational modeling, and closed-loop feedback control to simulate a cellular conductance. Here, we present two example applications: artificial blocking of the inward rectifier potassium current in a cardiomyocyte and coupling of a biological neuron to a virtual neuron through a virtual synapse. The design and implementation of the necessary software to administer these dynamic clamp experiments can be difficult. In this chapter, we provide an overview of designing and implementing a dynamic clamp experiment using the Real-Time eXperiment Interface (RTXI), an open- source software system tailored for real-time biological experiments. We present two ways to achieve this using RTXI’s modular format, through the creation of a custom user-made module and through existing modules found in RTXI’s online library. PMID:25023319

Papilloma diagnosed at MRI-guided vacuum-assisted breast biopsy: is surgical excision still warranted?

PubMed

Brennan, Sandra B; Corben, Adriana; Liberman, Laura; Dershaw, D David; Brogi, Edi; Van Zee, Kimberly J; Morris, Elizabeth

2012-10-01

The objective of our study was to determine the frequency of cancer at surgery in breast lesions yielding papilloma at MRI-guided 9-gauge vacuum-assisted biopsy (VAB) and to determine whether any features are associated with cancer upgrade. For this study, 1487 MRI-guided vacuum-assisted biopsies performed from January 2004 to March 2011 were reviewed. Lesions yielding papilloma were identified and classified as papilloma with or without atypia. Surgical findings were reviewed to determine the cancer rate. Statistical analysis was performed and 95% CIs were calculated. Papilloma was identified in 75 of the 1487 MRI-guided vacuum-assisted biopsies (5%). These 75 papillomas occurred in 73 women with a median age of 49 years (age range, 27-70 years). Of the 75 papillomas, 25 (33%) had atypia and 50 (67%) did not on core needle biopsy. Subsequent surgery of 67 of the 75 papillomas (89%) yielded ductal carcinoma in situ (DCIS) in four (6%; 95% CI, 2-15%). Surgery yielded DCIS in two of 23 papillomas with atypia (9%; 95% CI, 1-28%) at MRI-guided VAB and in two of 44 papillomas without atypia (5%; 95% CI, 0.4-16%) at MRI-guided VAB; these cancer rates did not differ significantly (p=0.6). Postmenopausal status (p=0.04) and histologic size of less than 0.2 cm (p=0.04) had a significant association with the cancer upgrade rate. Papilloma with or without atypia was found in 5% of patients who underwent MRI-guided VAB during the study period. Surgery revealed cancer in 6%. DCIS was found at surgery in 9% of lesions yielding papilloma with atypia versus 5% of lesions yielding papilloma without atypia. For lesions yielding papilloma with or without atypia at MRI-guided VAB, surgical excision is warranted.

Testing of Diode-Clamping in an Inductive Pulsed Plasma Thruster Circuit

NASA Technical Reports Server (NTRS)

Toftul, Alexandra; Polzin, Kurt A.; Martin, Adam K.; Hudgins, Jerry L.

2014-01-01

Testing of a 5.5 kV silicon (Si) diode and 5.8 kV prototype silicon carbide (SiC) diode in an inductive pulsed plasma thruster (IPPT) circuit was performed to obtain a comparison of the resulting circuit recapture efficiency,eta(sub r), defined as the percentage of the initial charge energy remaining on the capacitor bank after the diode interrupts the current. The diode was placed in a pulsed circuit in series with a silicon controlled rectifier (SCR) switch, and the voltages across different components and current waveforms were collected over a range of capacitor charge voltages. Reverse recovery parameters, including turn-off time and peak reverse recovery current, were measured and capacitor voltage waveforms were used to determine the recapture efficiency for each case. The Si fast recovery diode in the circuit was shown to yield a recapture efficiency of up to 20% for the conditions tested, while the SiC diode further increased recapture efficiency to nearly 30%. The data presented show that fast recovery diodes operate on a timescale that permits them to clamp the discharge quickly after the first half cycle, supporting the idea that diode-clamping in IPPT circuit reduces energy dissipation that occurs after the first half cycle

Temperature-Controlled Clamping and Releasing Mechanism

NASA Technical Reports Server (NTRS)

Rosing, David; Ford, Virginia

2005-01-01

A report describes the development of a mechanism that automatically clamps upon warming and releases upon cooling between temperature limits of approx. =180 K and approx. =293 K. The mechanism satisfied a need specific to a program that involved repeated excursions of a spectrometer between a room-temperature atmospheric environment and a cryogenic vacuum testing environment. The mechanism was also to be utilized in the intended application of the spectrometer, in which the spectrometer would be clamped for protection during launch of a spacecraft and released in the cold of outer space to allow it to assume its nominal configuration for scientific observations. The mechanism is passive in the sense that its operation does not depend on a control system and does not require any power other than that incidental to heating and cooling. The clamping and releasing action is effected by bolt-preloaded stacks of shape-memory-alloy (SMA) cylinders. In designing this mechanism, as in designing other, similar SMA mechanisms, it was necessary to account for the complex interplay among thermal expansion, elastic and inelastic deformation under load, and SMA thermomechanical properties.

Biopsy of the buccal mucosa in oral lichen planus: the traditional method versus the use of a new pressure forceps.

PubMed

Bermejo-Fenoll, Ambrosio; López-Jornet, María Pía; Jiménez-Torres, María José; Camacho-Alonso, Fabio; Orduña-Domingo, Albina

2007-07-01

The authors designed a pressure forceps, called the "B forceps," for use in performing biopsies. They compared biopsy specimens taken with and without the aid of the B forceps from buccal mucosa of 84 patients divided equally into two groups, all of whom satisfied the World Health Organization's diagnostic criteria for oral lichen planus. They analyzed the advantages and disadvantages of using this instrument. The 42 patients in group A underwent a conventional biopsy (29 with a scalpel and 13 with a punch). The 42 patients in group B underwent a biopsy performed with the B forceps and a punch. The authors studied artifacts of fragmentation, pseudocysts, crushing, fissures and hemorrhages histologically in both groups. There were no significant differences within group A between the subjects who had undergone either the scalpel or the punch biopsy. There were, however, significant differences between groups A and B. Group B experienced less fragmentation (P = .021), fewer fissures (P = .001) and fewer hemorrhages (P = .001). The new B forceps was a useful aid in the performance of biopsies. It improved visibility and reduced the time needed for the procedure. Biopsy specimens taken with the B forceps also had histologically fewer artifacts than did those taken without the B forceps. This technique using the B forceps has several advantages, including speed, because the ischemia produced by the clamp stabilizes the tissue and increases visibility, facilitating dissection. The time needed for surgical removal thus is shortened.

Active energy recovery clamping circuit to improve the performance of power converters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whitaker, Bret; Barkley, Adam

2017-05-09

A regenerative clamping circuit for a power converter using clamping diodes to transfer charge to a clamping capacitor and a regenerative converter to transfer charge out of the clamping capacitor back to the power supply input connection. The regenerative converter uses a switch connected to the midpoint of a series connected inductor and capacitor. The ends of the inductor and capacitor series are connected across the terminals of the power supply to be in parallel with the power supply.

Kidney Biopsy

MedlinePlus

... Series Urinary Tract Imaging Urodynamic Testing Virtual Colonoscopy Kidney Biopsy What is a kidney biopsy? A kidney biopsy is a procedure that ... performs procedures using imaging equipment Why is a kidney biopsy performed? A health care provider will perform ...

Intra-patient comparison of parietal pleural biopsies by rigid forceps, flexible forceps and cryoprobe obtained during medical thoracoscopy: a prospective series of 80 cases with pleural effusion.

PubMed

Wurps, H; Schönfeld, N; Bauer, T T; Bock, M; Duve, C; Sauer, R; Mairinger, T; Griff, S

2016-07-07

There is only few data available on the use of cryotechnique during medical thoracoscopy. Medical thoracoscopy was performed in consecutive patients with pleural effusion. Prospectively, biopsies were taken by rigid forceps, flexible forceps and cryoprobe. Specimen size, depth and diagnostic yield were compared. 80 Patients were included. 408 biopsies were taken (205 rigid biopsies, 104 flexible biopsies, 99 cryobiopsies). Mean surface area of rigid biopsies was 22.6 ± 20.4 mm(2) (flexible biopsies: 7.1 ± 9.3 mm(2), cryobiopsies: 14.4 ± 12.8 mm(2)). Rigid biopsies were significantly larger than cryobiopsies (p < 0.001) and flexible biopsies (p < 0.001), crybiopsies were significantly larger than flexible biopsies (p < 0.01). A deep biopsy containing fatty tissue was harvested in 63 % of rigid biopsies (cryobiopsy: 49.5 % flexible biopsy: 39.5 %). In 79/80 cases (98.7 % 95 % CI cannot be calculated) a diagnosis was obtained by rigid biopsy (cryobiopsy: 73/80 cases (91.3 % 95 % CI 86.0 - 96.5 %), flexible biopsy: 74/80 cases (92.5 % 95 % CI 88.6 - 97.4 %)). Diagnostic yield achieved with cryobiopsies was inferior to the yield of rigid biopsies (Difference: 12.7 %), but non-inferior to flexible biopsies (Difference: 6.5 %). Cryobiopsies in medical thoracoscopy are safe with high diagnostic yield, non-inferior to flexible biopsies with increased tissue quantity and quality. Cryotechnique can develop an important role in medical thoracoscopy in the near future when rigid thoracoscopy is not available.

[Telomerase in lung cancer. Testing the activity of the "immortaligy enzyme" bronchial biopsies increases the diagnostic yield in cases of suspected peripheral bronchogenic carcinomas].

PubMed

Freitag, L; Litterst, P; Obertrifter, B; Velehorschi, V; Kemmer, H P; Linder, A; Brightman, I

2000-11-01

The proliferative capability is time-limited in normal somatic cells by the shortening of their chromosomal ends, the telomeres (Hayflick limit). An important feature of malignant cells is their immortality. The probably most common mechanism of tumour cells to achieve unlimited replicability is the activation of the enzyme telomerase. The reverse transcriptase can compensate the loss of telomeres. Using a PCR-based TRAP assay we found telomerase activity in tumour biopsies, exsudates and bronchial washings in various thoracic malignancies. In 38 of 47 patients with suspected peripheral lung cancer eventually surgery or invasive procedures proved a malignancy. In fluoroscopically guided bronchial brushings from 25 of these 38 patients (66%) the TRAP assay revealed telomerase activity. There was a single false positive case (tuberculosis) and with a single exception, the simultaneously taken brushes of the contralateral lobes were all telomerase negative. In 23 patients (61%) tumour cells were found in the cytological examination. In 33 patients at least one marker was positive. Thus the combination of cytology and telomerase test in bronchial brush biopsies attained a diagnostic yield of 87%.

Microchip amplifier for in vitro, in vivo, and automated whole cell patch-clamp recording

PubMed Central

Kolb, Ilya; Kodandaramaiah, Suhasa B.; Chubykin, Alexander A.; Yang, Aimei; Bear, Mark F.; Boyden, Edward S.; Forest, Craig R.

2014-01-01

Patch clamping is a gold-standard electrophysiology technique that has the temporal resolution and signal-to-noise ratio capable of reporting single ion channel currents, as well as electrical activity of excitable single cells. Despite its usefulness and decades of development, the amplifiers required for patch clamping are expensive and bulky. This has limited the scalability and throughput of patch clamping for single-ion channel and single-cell analyses. In this work, we have developed a custom patch-clamp amplifier microchip that can be fabricated using standard commercial silicon processes capable of performing both voltage- and current-clamp measurements. A key innovation is the use of nonlinear feedback elements in the voltage-clamp amplifier circuit to convert measured currents into logarithmically encoded voltages, thereby eliminating the need for large high-valued resistors, a factor that has limited previous attempts at integration. Benchtop characterization of the chip shows low levels of current noise [1.1 pA root mean square (rms) over 5 kHz] during voltage-clamp measurements and low levels of voltage noise (8.2 μV rms over 10 kHz) during current-clamp measurements. We demonstrate the ability of the chip to perform both current- and voltage-clamp measurement in vitro in HEK293FT cells and cultured neurons. We also demonstrate its ability to perform in vivo recordings as part of a robotic patch-clamping system. The performance of the patch-clamp amplifier microchip compares favorably with much larger commercial instrumentation, enabling benchtop commoditization, miniaturization, and scalable patch-clamp instrumentation. PMID:25429119

Bone Marrow Biopsy: RNA Isolation with Expression Profiling in Men with Metastatic Castration-resistant Prostate Cancer—Factors Affecting Diagnostic Success

PubMed Central

Afonso, P. Diana; Vinson, Emily N.; Turnbull, James D.; Morris, Karla K.; Foye, Adam; Madden, John F.; Roy Choudhury, Kingshuk; Febbo, Phillip G.; George, Daniel J.

2013-01-01

Purpose To determine the rate at which computed tomographically guided pelvic percutaneous bone biopsy in men with metastatic castration-resistant prostate cancer (mCRPC) yields adequate tissue for genomic profiling and to identify issues likely to affect diagnostic yields. Materials and Methods This study was institutional review board approved, and written informed consent was obtained. In a phase II trial assessing response to everolimus, 31 men with mCRPC underwent 54 biopsy procedures (eight men before and 23 men both before and during treatment). Variables assessed were lesion location (iliac wing adjacent to sacroiliac joint, iliac wing anterior and/or superior to sacroiliac joint, sacrum, and remainder of pelvis), mean lesion attenuation, subjective lesion attenuation (purely sclerotic vs mixed), central versus peripheral lesion sampling, lesion size, core number, and use of zoledronic acid for more than 1 year. Results Of 54 biopsy procedures, 21 (39%) yielded adequate tissue for RNA isolation and genomic profiling. Three of four sacral biopsies were adequate. Biopsies of the ilium adjacent to the sacroiliac joints were more likely adequate than those from elsewhere in the ilium (48% vs 28%, respectively). All five biopsies performed in other pelvic locations yielded inadequate tissue for RNA isolation. Mean attenuation of lesions with inadequate tissue was 172 HU greater than those with adequate tissue (621.1 HU ± 166 vs 449 HU ± 221, respectively; P = .002). Use of zoledronic acid, peripheral sampling, core number, and lesion size affected yields, but the differences were not statistically significant. Histologic examination with hematoxylin-eosin staining showed that results of 36 (67%) biopsies were positive for cancer; only mean attenuation differences were significant (707 HU ± 144 vs 473 HU ± 191, negative vs positive, respectively; P < .001). Conclusion In men with mCRPC, percutaneous sampling of osseous metastases for genomic profiling is

Robotic partial nephrectomy with selective parenchymal compression (Simon clamp).

PubMed

Castillo, O A; Rodriguez-Carlin, A; Lopez-Fontana, G; Aleman, E

2013-01-01

To present our initial experience using selective renal parenchymal ischemia, without hilar clamping, in robotic-assisted partial nephrectomy. In four patients with T1a renal tumor we performed robotic-assisted partial nephrectomy, using the Simon's clamp (Aesculap). It provides selective parenchymal compression without the need of vascular clamping. All patients had exofitic renal tumors in polar location. Renal parenchymal reconstruction was done as the standard technique. The median age was 49.6 years (42-59), 3 male and 1 female patient. Median operative time was 71,6 minutes (40-120). Mean stimated bleeding was 250 ml (50-400). Average tumor size was 3,25 cm (1,5-5,3). There were no complications and the average hospital stay was 3,5 days (1-7). The pathology was informed as renal cell carcinoma in three patients and one hemorrhagic cyst. The surgical margins were negative. Our preliminary results shows that selective renal parenchymal compression, with the Simon's clamp, provides an alternative to vascular control in selected patients with polar renal tumors. Copyright © 2012 AEU. Published by Elsevier Espana. All rights reserved.

Fluoroscopy-Guided Percutaneous Vertebral Body Biopsy Using a Novel Drill-Powered Device: Technical Case Series

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wallace, Adam N., E-mail: wallacea@mir.wustl.edu; Pacheco, Rafael A., E-mail: pachecor@mir.wustl.edu; Tomasian, Anderanik, E-mail: tomasiana@mir.wustl.edu

2016-02-15

BackgroundA novel coaxial biopsy system powered by a handheld drill has recently been introduced for percutaneous bone biopsy. This technical note describes our initial experience performing fluoroscopy-guided vertebral body biopsies with this system, compares the yield of drill-assisted biopsy specimens with those obtained using a manual technique, and assesses the histologic adequacy of specimens obtained with drill assistance.MethodsMedical records of all single-level, fluoroscopy-guided vertebral body biopsies were reviewed. Procedural complications were documented according to the Society of Interventional Radiology classification. The total length of bone core obtained from drill-assisted biopsies was compared with that of matched manual biopsies. Pathology reportsmore » were reviewed to determine the histologic adequacy of specimens obtained with drill assistance.ResultsTwenty eight drill-assisted percutaneous vertebral body biopsies met study inclusion criteria. No acute complications were reported. Of the 86 % (24/28) of patients with clinical follow-up, no delayed complications were reported (median follow-up, 28 weeks; range 5–115 weeks). The median total length of bone core obtained from drill-assisted biopsies was 28 mm (range 8–120 mm). This was longer than that obtained from manual biopsies (median, 20 mm; range 5–45 mm; P = 0.03). Crush artifact was present in 11 % (3/28) of drill-assisted biopsy specimens, which in one case (3.6 %; 1/28) precluded definitive diagnosis.ConclusionsA drill-assisted, coaxial biopsy system can be used to safely obtain vertebral body core specimens under fluoroscopic guidance. The higher bone core yield obtained with drill assistance may be offset by the presence of crush artifact.« less

Transthoracic needle biopsy of the lung

PubMed Central

DiBardino, David M.; Yarmus, Lonny B.

2015-01-01

Background Image guided transthoracic needle aspiration (TTNA) is a valuable tool used for the diagnosis of countless thoracic diseases. Computed tomography (CT) is the most common imaging modality used for guidance followed by ultrasound (US) for lesions abutting the pleural surface. Novel approaches using virtual CT guidance have recently been introduced. The objective of this review is to examine the current literature for TTNA biopsy of the lung focusing on diagnostic accuracy and safety. Methods MEDLINE was searched from inception to October 2015 for all case series examining image guided TTNA. Articles focusing on fluoroscopic guidance as well as influence of rapid on-site evaluation (ROSE) on yield were excluded. The diagnostic accuracy, defined as the number of true positives divided by the number of biopsies done, as well as the complication rate [pneumothorax (PTX), bleeding] was examined for CT guided TTNA, US guided TTNA as well as CT guided electromagnetic navigational-TTNA (E-TTNA). Of the 490 articles recovered 75 were included in our analysis. Results The overall pooled diagnostic accuracy for CT guided TTNA using 48 articles that met the inclusion and exclusion criteria was 92.1% (9,567/10,383). A similar yield was obtained examining ten articles using US guided TTNA of 88.7% (446/503). E-TTNA, being a new modality, only had one pilot study citing a diagnostic accuracy of 83% (19/23). Pooled PTX and hemorrhage rates were 20.5% and 2.8% respectively for CT guided TTNA. The PTX rate was lower in US guided TTNA at a pooled rate of 4.4%. E-TTNA showed a similar rate of PTX at 20% with no incidence of bleeding in a single pilot study available. Conclusions Image guided TTNA is a safe and accurate modality for the biopsy of lung pathology. This study found similar yield and safety profiles with the three imaging modalities examined. PMID:26807279

Complications and adequacy of transplant kidney biopsies: A comparison of techniques.

PubMed

Plattner, Brett W; Chen, Pauline; Cross, Richard; Leavitt, Matthew A; Killen, Paul D; Heung, Michael

2018-05-01

Kidney biopsies are an essential tool in the diagnosis and management of kidney diseases, particularly in kidney transplant recipients. Biopsies carry a risk for serious complications and not all biopsies achieve adequate tissue. We examined the impact of kidney biopsy technique on complications and biopsy adequacy. The cohort consisted of consecutive kidney transplant patients undergoing biopsy by one of three techniques: ultrasound localization, real-time ultrasound guidance, and ultrasound-guided trocar placement. Variables of interest included patient characteristics and procedural characteristics. The primary outcome was serious complication attributable to kidney biopsy, and the secondary outcome was biopsy adequacy as defined by Banff criteria. Among 263 patients undergoing biopsy, 27 (10.3%) had a complication (14 with gross hematuria, 10 requiring blood transfusion, 3 requiring an unplanned interventional radiology procedure, 1 kidney loss; no deaths). Complications were more common among patients biopsied using ultrasound-guided trocar compared to real-time ultrasound and ultrasound localization (21.4% vs 7.9% vs 7.1%, respectively, p = 0.008). After adjusting for patient and procedure characteristics, technique was no longer significantly associated with complication. Biopsy adequacy was significantly higher when using ultrasound localization and real-time ultrasound compared to ultrasound-guided trocar (84.6% vs 86.8% vs 69.6%, p = 0.029), and this finding persisted in adjusted analysis. Kidney biopsy complications appear to be similar when using any of the three techniques examined in our study. However, ultrasound-guided trocar technique may yield lower biopsy adequacy when compared to non-trocar techniques.

Skin lesion biopsy

MedlinePlus

... biopsy - skin; Skin cancer - biopsy; Melanoma - biopsy; Squamous cell cancer - biopsy; Basal cell cancer - biopsy; Mohs microsurgery ... dermatitis Infection from bacteria or fungus Melanoma Basal cell skin cancer Squamous cell skin cancer

[Analysis of brain hemometabolism behavior during carotid endarterectomy with temporary clamping.].

PubMed

Duval Neto, Gastão Fernandes; Niencheski, Augusto H

2004-04-01

Carotid endarterectomy with temporary clamping changes cerebral blood flow and cerebral metabolic oxygen demand ratio with consequent oligemic hypoxia or hemometabolic uncoupling. This study aimed at identifying changes in brain hemometabolism, evaluated through changes in oxyhemoglobin saturation in internal jugular vein bulb (SvjO2) during carotid endarterectomy with clamping, and at correlating these changes with potentially interfering factors, mainly end tidal CO2 pressure (P ET CO2) and cerebral perfusion pressure (CPP). Sixteen patients with unilateral carotid stenotic disease scheduled to carotid endarterectomy with carotid arterial clamping were enrolled in this study. Parameters including internal jugular bulb oxyhemoglobin saturation, stump pressure and end tidal CO2 pressure were measured at the following moments: M1 - pre-clamping; M2 - 3 minutes after clamping; M3 - pre-unclamping; M4 - post-unclamping). The comparison among SvjO2 (%, mean +/- SD) in all studied periods has shown differences between those recorded in moments M1 (52.25 +/- 7.87) and M2 (47.43 +/- 9.19). This initial decrease stabilized during temporary clamping, showing decrease in the comparison between M2 and M3 (46.56 +/- 9.25), without statistical significance (p = ns). At post-unclamping, M4 (47.68 +/- 9.12), SvjO2 was increased as compared to M2 and M3 clamping stages, however it was still lower than that of pre-clamping stage M1.(M4 x M1 - p < 0.04) This SvjO2 decrease was followed by significant cerebral perfusion pressure (stump pressure) decrease. Factors influencing this brain hemometabolic uncoupling trend were correlated to P ET CO2. The comparison between CPP and SvjO2 showed weak correlation devoid of statistical significance. In the conditions of our study, SvjO2 measurement is a fast and effective way of clinically monitoring changes in CBF/CMRO2 ratio. Temporary carotid clamping implies in a trend towards brain hemometabolic uncoupling and, as a consequence, to

CT-Guided Transgluteal Biopsy for Systematic Random Sampling of the Prostate in Patients Without Rectal Access.

PubMed

Goenka, Ajit H; Remer, Erick M; Veniero, Joseph C; Thupili, Chakradhar R; Klein, Eric A

2015-09-01

The objective of our study was to review our experience with CT-guided transgluteal prostate biopsy in patients without rectal access. Twenty-one CT-guided transgluteal prostate biopsy procedures were performed in 16 men (mean age, 68 years; age range, 60-78 years) who were under conscious sedation. The mean prostate-specific antigen (PSA) value was 11.4 ng/mL (range, 2.3-39.4 ng/mL). Six had seven prior unsuccessful transperineal or transurethral biopsies. Biopsy results, complications, sedation time, and radiation dose were recorded. The mean PSA values and number of core specimens were compared between patients with malignant results and patients with nonmalignant results using the Student t test. The average procedural sedation time was 50.6 minutes (range, 15-90 minutes) (n = 20), and the mean effective radiation dose was 8.2 mSv (median, 6.6 mSv; range 3.6-19.3 mSv) (n = 13). Twenty of the 21 (95%) procedures were technically successful. The only complication was a single episode of gross hematuria and penile pain in one patient, which resolved spontaneously. Of 20 successful biopsies, 8 (40%) yielded adenocarcinoma (Gleason score: mean, 8; range, 7-9). Twelve biopsies yielded nonmalignant results (60%): high-grade prostatic intraepithelial neoplasia (n = 3) or benign prostatic tissue with or without inflammation (n = 9). Three patients had carcinoma diagnosed on subsequent biopsies (second biopsy, n = 2 patients; third biopsy, n = 1 patient). A malignant biopsy result was not significantly associated with the number of core specimens (p = 0.3) or the mean PSA value (p = 0.1). CT-guided transgluteal prostate biopsy is a safe and reliable technique for the systematic random sampling of the prostate in patients without a rectal access. In patients with initial negative biopsy results, repeat biopsy should be considered if there is a persistent rise in the PSA value.

Term babies with delayed cord clamping: an approach in preventing anemia (.).

PubMed

Ertekin, Arif Aktug; Nihan Ozdemir, Nilufer; Sahinoglu, Zeki; Gursoy, Tugba; Erbil, Nazan; Kaya, Erdal

2016-09-01

We investigated the effects of delayed and early clamping of the cord on the hematologic status of the baby at birth and at the end of second month. Umbilical cord of 74 babies were clamped in the first 30 s (Group 1) and 76 were clamped at 90-120 s (Group 2). Levels of hemoglobin, hematocrit, iron and ferritin were analyzed from the umbilical cord blood at birth and from the venous samples at the end of second month. Hemoglobin, hematocrit, iron and ferritin levels of cord blood were similar in both groups. However, their levels other than ferritin were higher in Group 2 at the end of second month. Two babies had respiratory distress and twelve neonates received phototherapy in Group 2 whereas only five neonates received phototherapy in Group 1. Term babies to whom delayed cord clamping was performed had improved hematological parameters at the end of second month. Therefore, delaying cord clamping in these babies may be a favorible approach in preventing anemia.

Electrostatic Interactions at the Dimer Interface Stabilize the E. coli β Sliding Clamp.

PubMed

Purohit, Anirban; England, Jennifer K; Douma, Lauren G; Tondnevis, Farzaneh; Bloom, Linda B; Levitus, Marcia

2017-08-22

Sliding clamps are ring-shaped oligomeric proteins that encircle DNA and associate with DNA polymerases for processive DNA replication. The dimeric Escherichia coli β-clamp is closed in solution but must adopt an open conformation to be assembled onto DNA by a clamp loader. To determine what factors contribute to the stability of the dimer interfaces in the closed conformation and how clamp dynamics contribute to formation of the open conformation, we identified conditions that destabilized the dimer and measured the effects of these conditions on clamp dynamics. We characterized the role of electrostatic interactions in stabilizing the β-clamp interface. Increasing salt concentration results in decreased dimer stability and faster subunit dissociation kinetics. The equilibrium dissociation constant of the dimeric clamp varies with salt concentration as predicted by simple charge-screening models, indicating that charged amino acids contribute to the remarkable stability of the interface at physiological salt concentrations. Mutation of a charged residue at the interface (Arg-103) weakens the interface significantly, whereas effects are negligible when a hydrophilic (Ser-109) or a hydrophobic (Ile-305) amino acid is mutated instead. It has been suggested that clamp opening by the clamp loader takes advantage of spontaneous opening-closing fluctuations at the clamp's interface, but our time-resolved fluorescence and fluorescence correlation experiments rule out conformational fluctuations that lead to a significant fraction of open states. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Micro-array isolation of circulating tumor cells (CTCs): the droplet biopsy chip

NASA Astrophysics Data System (ADS)

Panchapakesan, B.

2017-08-01

We present a new method for circulating tumor cell capture based on micro-array isolation from droplets. Called droplet biopsy, our technique uses a 76-element array of carbon nanotube devices functionalized with anti-EpCAM and antiHer2 antibodies for immunocapture of spiked breast cancer cells in the blood. This droplet biopsy chip can enable capture of CTCs based on both positive and negative selection strategy. Negative selection is achieved through depletion of contaminating leukocytes through the differential settling of blood into layers. We report 55%-100% cancer cell capture yield in this first droplet biopsy chip study. The droplet biopsy is an enabling idea where one can capture CTCs based on multiple biomarkers in a single blood sample.

Utility of core biopsy with concurrent ROSE FNA in the diagnosis of pancreatic tumor-does the biopsy add any diagnostic benefit?

PubMed

Yan, Lei; Ikemura, Kenji; Park, Ji-Weon

2018-02-01

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided core-needle biopsy (EUS-CNB) are widely used for diagnosis of pancreatic tumors. The aim of our study was to compare the diagnostic performance of ROSE EUS-FNA and EUS-CNB for diagnosis of pancreatic malignancy during the same EUS. Patients who underwent both FNA and CNB during the same EUS for pancreatic solid lesion were reviewed retrospectively. Sample adequacy, diagnostic yield (defined as percentage of definitive diagnosis), sensitivity and specificity for malignancy were compared between FNA and CNB. A total of 48 patients with solid pancreatic lesions were evaluated. The proportions of adequate samples were 48/48 (100%) for FNA and 45/48 (93.7%) for core biopsy (P = .24). The diagnostic yield was 42/48 (87.5%) and 33/48 (68.7%) for FNA and CNB respectively (P = .046). The incremental increase in diagnostic yield by combining both methods was 2/48 (4%). The diagnostic yield for malignancy was 30/32 (93.7%) for FNA and 23/32 (71.8%) for CNB (P = .043). The sensitivity for the diagnosis of malignancy for FNA and CNB were 90.6% and 69%, respectively (P = .045). The specificity was 100% for both methods. The sensitivity for diagnosing malignancy increased to 93.8% when the two methods were combined. The difference in diagnostic yield was not associated with lesion size or location. EUS-guided FNA is a superior method of assessing solid pancreatic lesion and pancreatic malignancy with better diagnostic yield and higher sensitivity than EUS-CNB. © 2017 Wiley Periodicals, Inc.

Renal Vascular Clamp Placement: A Potential Cause of Incomplete Hilar Control during Partial Nephrectomy.

PubMed

Tryon, David; Myklak, Kristene; Alsyouf, Muhannad; Conceicao, Carol; Peplinski, Brandon; Arenas, Javier L; Faaborg, Daniel; Ruckle, Herbert C; Baldwin, D Duane

2016-03-01

Previous benchtop studies have shown that robotic bulldog clamps provide incomplete vascular control of a Penrose drain. We determined the efficacy of robotic and laparoscopic bulldog clamps to ensure hemostasis on the human renal artery. The effect of clamp position on vascular control was also examined. Fresh human cadaveric renal arteries were used to determine the leak point pressure of 7 bulldog clamps from a total of 3 manufacturers. Five trials were performed per clamp at 4 locations, including the fulcrum, proximal, middle and distal positions. Comparison was done using the Kruskal-Wallis test with p <0.05 considered significant. None of the bulldog clamps leaked at a pressure less than 215 mm Hg when applied at the proximal, middle or distal position. In general leak point pressure decreased as the artery was positioned more distal along the clamp. The exception was when the vessel was placed at the fulcrum position. At that position 80% to 100% of trials with the Klein laparoscopic, 100% with the Klein robotic (Klein Robotic, San Antonio, Texas) and 60% to 80% with the Scanlan robotic (Scanlan International, Saint Paul, Minnesota) clamp leaked at pressure below 215 mm Hg. Each vascular clamp adequately occluded flow at physiological pressure when placed at the proximal, middle or distal position. Furthermore, these results demonstrate that there is leakage at physiological pressure when the artery is placed at the fulcrum of certain clamp types. These results suggest that applying a bulldog clamp at the fulcrum could potentially lead to inadequate vessel occlusion and intraoperative bleeding. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

A Dynamic Clamp on Every Rig

PubMed Central

2017-01-01

Abstract The dynamic clamp should be a standard part of every cellular electrophysiologist’s toolbox. That it is not, even 25 years after its introduction, comes down to three issues: money, the disruption that adding dynamic clamp to an existing electrophysiology rig entails, and the technical prowess required of experimenters. These have been valid and limiting issues in the past, but no longer. Technological advances associated with the so-called maker movement render them moot. We demonstrate this by implementing a fast (∼100 kHz) dynamic clamp system using an inexpensive microcontroller (Teensy 3.6). The overall cost of the system is less than USD$100, and assembling it requires no prior electronics experience. Modifying it—for example, to add Hodgkin–Huxley-style conductances—requires no prior programming experience. The system works together with existing electrophysiology data acquisition systems (for Macintosh, Windows, and Linux); it does not attempt to supplant them. Moreover, the process of assembling, modifying, and using the system constitutes a useful pedagogical exercise for students and researchers with no background but an interest in electronics and programming. We demonstrate the system’s utility by implementing conductances as fast as a transient sodium conductance and as complex as the Ornstein–Uhlenbeck conductances of the “point conductance” model of synaptic background activity. PMID:29085905

Peptide- and proton-driven allosteric clamps catalyze anthrax toxin translocation across membranes

PubMed Central

Das, Debasis; Krantz, Bryan A.

2016-01-01

Anthrax toxin is an intracellularly acting toxin in which sufficient information is available regarding the structure of its transmembrane channel, allowing for detailed investigation of models of translocation. Anthrax toxin, comprising three proteins—protective antigen (PA), lethal factor (LF), and edema factor—translocates large proteins across membranes. Here we show that the PA translocase channel has a transport function in which its catalytic active sites operate allosterically. We find that the phenylalanine clamp (ϕ-clamp), the known conductance bottleneck in the PA translocase, gates as either a more closed state or a more dilated state. Thermodynamically, the two channel states have >300-fold different binding affinities for an LF-derived peptide. The change in clamp thermodynamics requires distant α-clamp and ϕ-clamp sites. Clamp allostery and translocation are more optimal for LF peptides with uniform stereochemistry, where the least allosteric and least efficiently translocated peptide had a mixed stereochemistry. Overall, the kinetic results are in less agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an allosteric helix-compression model that is dependent also on substrate peptide coil-to-helix/helix-to-coil cooperativity. PMID:27506790

30 CFR 77.603 - Clamping of trailing cables to equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 77.603 Section 77.603 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... UNDERGROUND COAL MINES Trailing Cables § 77.603 Clamping of trailing cables to equipment. Trailing cables...

A monolithic patch-clamping amplifier with capacitive feedback.

PubMed

Prakash, J; Paulos, J J; Jensen, D N

1989-03-01

Patch-clamping is an established method for directly measuring ionic transport through cellular membranes with sufficient resolution to observe open/close transitions of individual channel molecules. This paper describes an alternative technique for patch-clamping which uses a capacitor as the transimpedance element. This approach eliminates bandwidth and saturation limitations experienced with resistive patch-clamping amplifiers. A complete monolithic design featuring an on-chip operational amplifier, a capacitor array with gain-ranging from 30 pF down to 0.03 pF, and reset and gain ranging switches has been fabricated using 5 microns CMOS technology. It is shown that the voltage noise of the CMOS operational amplifier limits the overall noise performance, but that performance competitive with conventional instruments can be achieved over a 10 kHz bandwidth, at least for small input capacitances (less than or equal to 5 pF). Results are presented along with an analysis and comparison of noise performance using both resistive and capacitive elements.

Open-access microfluidic patch-clamp array with raised lateral cell trapping sites.

PubMed

Lau, Adrian Y; Hung, Paul J; Wu, Angela R; Lee, Luke P

2006-12-01

A novel open-access microfluidic patch-clamp array chip with lateral cell trapping sites raised above the bottom plane of the chip was developed by combining both a microscale soft-lithography and a macroscale polymer fabrication method. This paper demonstrates the capability of using such an open-access fluidic system for patch-clamp measurements. The surface of the open-access patch-clamp sites prepared by the macroscale hole patterning method of soft-state elastic polydimethylsiloxane (PDMS) is examined; the seal resistances are characterized and correlated with the aperture dimensions. Whole cell patch-clamp measurements are carried out with CHO cells expressing Kv2.1 ion channels. Kv2.1 ion channel blocker (TEA) dosage response is characterized and the binding activity is examined. The results demonstrate that the system is capable of performing whole cell measurements and drug profiling in a more efficient manner than the traditional patch-clamp set-up.

Measuring beta-cell function relative to insulin sensitivity in youth: Does the hyperglycemic clamp suffice?

USDA-ARS?s Scientific Manuscript database

To compare beta-cell function relative to insulin sensitivity, disposition index (DI), calculated from two clamps (2cDI, insulin sensitivity from the hyperinsulinemic-euglycemic clamp and first-phase insulin from the hyperglycemic clamp) with the DI calculated from the hyperglycemic clamp alone (hcD...

Endometrial biopsy

MedlinePlus

... Names Biopsy - endometrium Images Pelvic laparoscopy Female reproductive anatomy Endometrial biopsy Uterus Endometrial biopsy References Beard JM, Osborn J. Common office procedures. In: Rakel RE, Rakel DP, eds. Textbook of Family Medicine . 9th ed. Philadelphia, PA: Elsevier ...

Percutaneous ultrasound-guided renal biopsy: A Libyan experience

PubMed Central

Mishra, A.; Tarsin, R.; ElHabbash, B.; Zagan, N.; Markus, R.; Drebeka, S.; AbdElmola, K.; Shawish, T.; Shebani, A.; AbdElmola, T.; ElUsta, A.; Ehtuish, E. F.

2010-01-01

This study was done to assess the safety and efficacy of ultrasound-guided percutaneous renal biopsy (PRB), to ascertain the risk factors for complications and determine the optimal period of observation. The radiologist (A.M.) at the National Organ Transplant Centre, Central Hospital, Tripoli, Libya, performed 86 PRBs between February 1, 2006, and January 31, 2008, using an automated biopsy gun with 16-gauge needle. Coagulation profile was done in all the patients. All patients were kept on strict bed rest for six hours post-procedure. Eighty six renal biopsies were performed on 78 patients referred from rheumatology department and eight post-kidney transplant recipients; 23 were males with age range 15 – 56 years and 63 females with age range 16 – 66 years. A mean of 17.5 glomeruli were present in each specimen. A glomerular yield of less than five glomeruli was seen in four biopsies. Class I lupus nephritis (LN) was seen in 1 patient, class II lupus nephritis in 7 patients, class III LN in 13 patients and class IV LN in 29 patients. All the eight renal allografts were diagnosed as acute tubular necrosis or acute interstitial rejection. The risk of post-biopsy bleeding was higher in women, older patients and higher PTT. The overall complication rate was 5.8%. Three complications were observed within six hours of biopsy. No late complication was seen. PRB under real-time ultrasound-guidance is a safe and efficacious procedure to establish the histological diagnosis and should be done as out-patient procedure. Observation time of six hours post-biopsy is optimal. PMID:20835320

Skin Biopsy

MedlinePlus

... Staying Safe Videos for Educators Search English Español Skin Biopsy KidsHealth / For Teens / Skin Biopsy What's in ... en español Biopsia de piel What Is a Skin Biopsy and Who Would Need One? In a ...

FDG-PET in the selection of brain lesions for biopsy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanson, M.W.; Glantz, M.J.; Hoffman, J.M.

1991-09-01

The CT-guided stereotaxic needle biopsy has become a widely used procedure in the diagnostic evaluation of intracranial lesions including tumors. Conventional CT or MR frequently defines the anatomic regions of abnormality, which may be multiple lesions or a single lesion that is heterogeneous in cellular composition owing to the topographic variation of cellular constituency or the combination of active disease, nonspecific inflammation, necrosis, and/or edema. In these cases, selection of the most appropriate site for a successful diagnostic needle biopsy can be difficult. In three patients, we have used (18F)fluorodeoxyglucose (FDG) positron emission tomography (PET) to determine the site mostmore » likely to provide a diagnostic biopsy result. In the first patient, who presented with confusion, multiple biopsies from the temporal lobe, based on MR abnormalities, revealed only reactive gliosis and edema. Repeat biopsy directed by PET revealed an anaplastic astrocytoma. In a second patient, PET allowed us to differentiate radiation effect from active metastatic breast cancer. In the third patient, who presented with a grand mal seizure, biopsy of a CT-defined hypodense region demonstrated lymphocytosis. Metabolism of FDG was normal or increased in areas of Aspergillus encephalitis at autopsy. These preliminary studies suggest a complementary role for FDG-PET and CT or MR in selected patients for defining the intracranial site most likely to yield a positive biopsy result.« less

Computer-assisted brush-biopsy analysis for the detection of dysplasia in a high-risk Barrett's esophagus surveillance population.

PubMed

Anandasabapathy, Sharmila; Sontag, Stephen; Graham, David Y; Frist, Stephen; Bratton, Joan; Harpaz, Noam; Waye, Jerome D

2011-03-01

Barrett's epithelial dysplasia, the direct precursor to esophageal adenocarcinoma, is often unapparent and frequently missed during surveillance of Barrett's esophagus with four-quadrant forceps biopsy protocol. To determine whether the detection of dysplasia is improved by adding computer-assisted brush biopsy (EndoCDx©) to four-quadrant biopsy protocol. Patients with a history of Barrett's esophagus with dysplasia scheduled for endoscopic surveillance were recruited from four academic medical centers. Patients underwent brush biopsy followed by four-quadrant biopsy every 1-2 cm. The results from brush and forceps biopsy were reviewed independently by pathologists blinded to the other's results. Among 151 patients enrolled (124 men, 27 women; mean age: 65), 117 (77.5%) had forceps and brush-biopsy specimens adequate for interpretation. The mean number of forceps biopsies was 11.9 (median 10, range 2-40) and brush biopsies was 2.0 (median 2, range 1-4). The overall yield of forceps alone was 25.2% (n = 38). Brush biopsy added an additional 16 positive cases increasing the yield of dysplasia detection by 42% (95% CI: 20.7-72.7). The number needed to test (NNT) to detect one additional case of dysplasia was 9.4 (95% CI: 6.4-17.7). There were no significant differences in results among different centers, between standard versus jumbo forceps, or between forceps biopsies taken every 1 cm versus every 2 cm. These data suggest that computer-assisted brush biopsy is a useful adjunct to standard endoscopic surveillance regimens for the identification of dysplasia in Barrett's esophagus.

Issues and challenges associated with classifying neoplasms in percutaneous needle biopsies of incidentally found small renal masses.

PubMed

Evans, Andrew J; Delahunt, Brett; Srigley, John R

2015-03-01

Percutaneous needle core biopsy has become acceptable for classifying renal tumours and guiding patient management in the setting of an incidentally-detected small renal mass (SRM), defined as an asymptomatic, non-palpable mass <4cm in maximum dimension. Long-held concerns preventing the incorporation of biopsies into routine patient care, including the perception of poor diagnostic yield and risks of complications such as bleeding or biopsy tract seeding, have largely been disproven. While needle biopsies for SRMs have traditionally been performed in academic centres, pathologists based in non-academic centres can expect to encounter these specimens as urologists and/or interventional radiologist trainees complete their training programs and begin work in non-academic centres. This review covers the rationale for performing these biopsies, the expected diagnostic yield, relevant differential diagnoses and an approach to classifying SRMs based on limited samples as well as the use of immunohistochemical (IHC) staining panels to aid in this process. There is also an undeniable learning curve for pathologists faced with reporting these biopsies and a number of issues and potential pitfalls attributable to sampling must be kept in mind by pathologists and clinicians alike. Copyright © 2015 Elsevier Inc. All rights reserved.

Micromolded PDMS planar electrode allows patch clamp electrical recordings from cells.

PubMed

Klemic, Kathryn G; Klemic, James F; Reed, Mark A; Sigworth, Fred J

2002-06-01

The patch clamp method measures membrane currents at very high resolution when a high-resistance 'gigaseal' is established between the glass microelectrode and the cell membrane (Pflugers Arch. 391 (1981) 85; Neuron 8 (1992) 605). Here we describe the first use of the silicone elastomer, poly(dimethylsiloxane) (PDMS), for patch clamp electrodes. PDMS is an attractive material for patch clamp recordings. It has low dielectric loss and can be micromolded (Annu. Rev. Mat. Sci. 28 (1998) 153) into a shape that mimics the tip of the glass micropipette. Also, the surface chemistry of PDMS may be altered to mimic the hydrophilic nature of glass (J. Appl. Polym. Sci. 14 (1970) 2499; Annu. Rev. Mat. Sci. 28 (1998) 153), thereby allowing a high-resistance seal to a cell membrane. We present a planar electrode geometry consisting of a PDMS partition with a small aperture sealed between electrode and bath chambers. We demonstrate that a planar PDMS patch electrode, after oxidation of the elastomeric surface, permits patch clamp recording on Xenopus oocytes. Our results indicate the potential for high-throughput patch clamp recording with a planar array of PDMS electrodes.

Dendrimer-assisted patch-clamp sizing of nuclear pores

PubMed Central

Bustamante, J.O.; Michelette, E.R.F.; Geibel, J.P.; Hanover, J.A.; McDonnell, T.J.; Dean, D.A.

2015-01-01

Macromolecular translocation (MMT) across the nuclear envelope (NE) occurs exclusively through the nuclear pore complex (NPC). Therefore, the diameter of the NPC aqueous/electrolytic channel (NPCC) is important for cellular structure and function. The NPCC diameter was previously determined to be ≅10 nm with electron microscopy (EM) using the translocation of colloidal gold particles. Here we present patch-clamp and fluorescence microscopy data from adult cardiomyocyte nuclei that demonstrate the use of patch-clamp for assessing NPCC diameter. Fluorescence microscopy with B-phycoerythrin (BPE, 240 kDa) conjugated to a nuclear localization signal (NLS) demonstrated that these nuclei were competent for NPC-mediated MMT (NPC-MMT). Furthermore, when exposed to an appropriate cell lysate, the nuclei expressed enhanced green fluorescence protein (EGFP) after 5–10 h of incubation with the plasmid for this protein (pEGFP, 3.1 MDa). Nucleus-attached patch-clamp showed that colloidal gold particles were not useful probes; they modified NPCC gating. As a result of this finding, we searched for an inert class of particles that could be used without irreversibly affecting NPCC gating and found that fluorescently labeled Star-burst dendrimers, a distinct class of polymers, were useful. Our patch-clamp and fluorescence microscopy data with calibrated dendrimers indicate that the cardiomyocyte NPCC diameter varies between 8 and 9 nm. These studies open a new direction in the investigation of live, continuous NPC dynamics under physiological conditions. PMID:10784359

Application of active electrode compensation to perform continuous voltage-clamp recordings with sharp microelectrodes.

PubMed

Gómez-González, J F; Destexhe, A; Bal, T

2014-10-01

Electrophysiological recordings of single neurons in brain tissues are very common in neuroscience. Glass microelectrodes filled with an electrolyte are used to impale the cell membrane in order to record the membrane potential or to inject current. Their high resistance induces a high voltage drop when passing current and it is essential to correct the voltage measurements. In particular, for voltage clamping, the traditional alternatives are two-electrode voltage-clamp technique or discontinuous single electrode voltage-clamp (dSEVC). Nevertheless, it is generally difficult to impale two electrodes in a same neuron and the switching frequency is limited to low frequencies in the case of dSEVC. We present a novel fully computer-implemented alternative to perform continuous voltage-clamp recordings with a single sharp-electrode. To reach such voltage-clamp recordings, we combine an active electrode compensation algorithm (AEC) with a digital controller (AECVC). We applied two types of control-systems: a linear controller (proportional plus integrative controller) and a model-based controller (optimal control). We compared the performance of the two methods to dSEVC using a dynamic model cell and experiments in brain slices. The AECVC method provides an entirely digital method to perform continuous recording and smooth switching between voltage-clamp, current clamp or dynamic-clamp configurations without introducing artifacts.

How to Interpret Thyroid Biopsy Results: A Three-Year Retrospective Interventional Radiology Experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oppenheimer, Jason D., E-mail: j-oppenheimer@md.northwestern.edu; Kasuganti, Deepa; Nayar, Ritu

2010-08-15

Results of thyroid biopsy determine whether thyroid nodule resection is appropriate and the extent of thyroid surgery. At our institution we use 20/22-gauge core biopsy (CBx) in conjunction with fine-needle aspiration (FNA) to decrease the number of passes and improve adequacy. Occasionally, both ultrasound (US)-guided FNA and CBx yield unsatisfactory specimens. To justify clinical recommendations for these unsatisfactory thyroid biopsies, we compare rates of malignancy at surgical resection for unsatisfactory biopsy results against definitive biopsy results. We retrospectively reviewed a database of 1979 patients who had a total of 2677 FNA and 663 CBx performed by experienced interventional radiologists undermore » US guidance from 2003 to 2006 at a tertiary-care academic center. In 451 patients who had surgery following biopsy, Fisher's exact test was used to compare surgical malignancy rates between unsatisfactory and malignant biopsy cohorts as well as between unsatisfactory and benign biopsy cohorts. We defined statistical significance at P = 0.05. We reported an overall unsatisfactory thyroid biopsy rate of 3.7% (100/2677). A statistically significant higher rate of surgically proven malignancies was found in malignant biopsy patients compared to unsatisfactory biopsy patients (P = 0.0001). The incidence of surgically proven malignancy in unsatisfactory biopsy patients was not significantly different from that in benign biopsy patients (P = 0.8625). In conclusion, an extremely low incidence of malignancy was associated with both benign and unsatisfactory thyroid biopsy results. The difference in incidence between these two groups was not statistically significant. Therefore, patients with unsatisfactory biopsy specimens can be reassured and counseled accordingly.« less

Magnetic Resonance and Ultrasound Image Fusion Supported Transperineal Prostate Biopsy Using the Ginsburg Protocol: Technique, Learning Points, and Biopsy Results.

PubMed

Hansen, Nienke; Patruno, Giulio; Wadhwa, Karan; Gaziev, Gabriele; Miano, Roberto; Barrett, Tristan; Gnanapragasam, Vincent; Doble, Andrew; Warren, Anne; Bratt, Ola; Kastner, Christof

2016-08-01

Prostate biopsy supported by transperineal image fusion has recently been developed as a new method to the improve accuracy of prostate cancer detection. To describe the Ginsburg protocol for transperineal prostate biopsy supported by multiparametric magnetic resonance imaging (mpMRI) and transrectal ultrasound (TRUS) image fusion, provide learning points for its application, and report biopsy results. The article is supplemented by a Surgery in Motion video. This single-centre retrospective outcome study included 534 patients from March 2012 to October 2015. A total of 107 had no previous prostate biopsy, 295 had benign TRUS-guided biopsies, and 159 were on active surveillance for low-risk cancer. A Likert scale reported mpMRI for suspicion of cancer from 1 (no suspicion) to 5 (cancer highly likely). Transperineal biopsies were obtained under general anaesthesia using BiopSee fusion software (Medcom, Darmstadt, Germany). All patients had systematic biopsies, two cores from each of 12 anatomic sectors. Likert 3-5 lesions were targeted with a further two cores per lesion. Any cancer and Gleason score 7-10 cancer on biopsy were noted. Descriptive statistics and positive predictive values (PPVs) and negative predictive values (NPVs) were calculated. The detection rate of Gleason score 7-10 cancer was similar across clinical groups. Likert scale 3-5 MRI lesions were reported in 378 (71%) of the patients. Cancer was detected in 249 (66%) and Gleason score 7-10 cancer was noted in 157 (42%) of these patients. PPV for detecting 7-10 cancer was 0.15 for Likert score 3, 0.43 for score 4, and 0.63 for score 5. NPV of Likert 1-2 findings was 0.87 for Gleason score 7-10 and 0.97 for Gleason score ≥4+3=7 cancer. Limitations include lack of data on complications. Transperineal prostate biopsy supported by MRI/TRUS image fusion using the Ginsburg protocol yielded high detection rates of Gleason score 7-10 cancer. Because the NPV for excluding Gleason score 7-10 cancer was very

Voltage-Clamp Studies on Uterine Smooth Muscle

PubMed Central

Anderson, Nels C.

1969-01-01

These studies have developed and tested an experimental approach to the study of membrane ionic conductance mechanisms in strips of uterine smooth muscle. The experimental and theoretical basis for applying the double sucrose-gap technique is described along with the limitations of this system. Nonpropagating membrane action potentials were produced in response to depolarizing current pulses under current-clamp conditions. The stepwise change of membrane potential under voltage-clamp conditions resulted in a family of ionic currents with voltage- and time-dependent characteristics. In sodium-free solution the peak transient current decreased and its equilibrium potential shifted along the voltage axis toward a more negative internal potential. These studies indicate a sodium-dependent, regenerative excitation mechanism. PMID:5796366

A nitric oxide concentration clamp.

PubMed

Zhelyaskov, V R; Godwin, D W

1999-10-01

We report a new method of generating nitric oxide (NO) that possesses several advantages for experimental use. This method consists of a photolysis chamber where NO is released by illuminating photolabile NO donors with light from a xenon lamp, in conjunction with feedback control. Control of the photolysis light was achieved by selectively gating light projected through a shutter before the light was launched into a light guide that conveyed the light to the photolysis chamber. By gating the light in proportion to a sensor that reported nearly instantaneous concentration from the photolysis chamber, a criterion NO concentration could be achieved, which could be easily adjusted to higher or lower criterion levels. To denote the similarity of this process with the electrophysiological process of voltage clamp, we term this process a concentration "clamp." This development enhances the use of the fiber-optic-based system for NO delivery and should enable the execution of experiments where the in situ concentration of NO is particularly critical, such as in biological preparations. Copyright 1999 Academic Press.

Targeted fascicular biopsy of the sciatic nerve and its major branches: rationale and operative technique.

PubMed

Capek, Stepan; Amrami, Kimberly K; Dyck, P James B; Spinner, Robert J

2015-09-01

OBJECT Nerve biopsy is typically performed in distal, noncritical sensory nerves without using imaging to target the more involved regions. The yield of these procedures rarely achieves more than 50%. In selected cases where preoperative evaluation points toward a more localized (usually a more proximal) process, targeted biopsy would likely capture the disease. Synthesis of data obtained from clinical examination, electrophysiological testing, and MRI allows biopsy of a portion of the major mixed nerves safely and efficiently. Herein, experiences with the sciatic nerve are reported and a description of the operative technique is provided. METHODS All cases of sciatic nerve biopsy performed between 2000 and 2014 were reviewed. Only cases of fascicular nerve biopsy approached from the buttock or the posterior aspect of the thigh were included. Demographic data, clinical presentation, and the presence of percussion tenderness for each patient were recorded. Reviewed studies included electrodiagnostic tests and imaging. Previous nerve and muscle biopsies were noted. All details of the procedure, final pathology, and its treatment implications were recorded. The complication rate was carefully assessed for temporary as well as permanent complications. RESULTS One hundred twelve cases (63 men and 49 women) of sciatic nerve biopsy were performed. Mean patient age was 46.4 years. Seventy-seven (68.8%) patients presented with single lower-extremity symptoms, 16 (14.3%) with bilateral lower-extremity symptoms, and 19 (17%) with generalized symptoms. No patient had normal findings on physical examination. All patients underwent electrodiagnostic studies, the findings of which were abnormal in 110 (98.2%) patients. MRI was available for all patients and was read as pathological in 111 (99.1%). The overall diagnostic yield of biopsy was 84.8% (n = 95). The pathological diagnoses included inflammatory demyelination, perineurioma, nonspecific inflammatory changes

Cantilever clamp fitting

NASA Technical Reports Server (NTRS)

Melton, Patrick B. (Inventor)

1989-01-01

A device is disclosed for sealing and clamping a cylindrical element which is to be attached to an object such as a wall, a pressurized vessel or another cylindrical element. The device includes a gland having an inner cylindrical wall, which is threaded at one end and is attached at a bendable end to a deformable portion, which in turn is attached to one end of a conical cantilever structure. The other end of the cantilever structure connects at a bendable area to one end of an outer cylindrical wall. The opposite end of cylindrical wall terminates in a thickened portion, the radially outer surface of which is adapted to accommodate a tool for rotating the gland. The terminal end of cylindrical wall also includes an abutment surface, which is adapted to engage a seal, which in turn engages a surface of a receiver. The receiver further includes a threaded portion for engagement with the threaded portion of gland whereby a tightening rotation of gland relative to receiver will cause relative movement between cylindrical walls and of gland. This movement causes a rotation of the conical structure and thus a bending action at bending area and at the bending end of the upper end of inner cylindrical wall. These rotational and bending actions result in a forcing of the deformable portion radially inwardly so as to contact and deform a pipe. This forcible contact creates a seal between gland and pipe, and simultaneously clamps the pipe in position.

Different protocols for cryobiopsy versus forceps biopsy in diagnosis of patients with endobronchial tumors.

PubMed

Jabari, Hamidreza; Sami, Ramin; Fakhri, Mohammad; Kiani, Arda

2012-01-01

Forceps biopsy is the standard procedure to obtain specimens in endobronchial lesions. New studies have proposed flexible cryoprobe as an accepted alternative method for this technique. Although diagnostic use of the cryobiopsy is confirmed in few studies, there is paucity of data with regard to an optimum protocol for this method since one of the main considerations in cryobiopsy is the freezing time. To evaluate diagnostic yield and safety of endobronchial biopsies using the flexible cryoprobe. Moreover, different freezing times were assessed to propose an optimized protocol for this diagnostic modality. For each patient with a confirmed intrabronchial lesion, diagnostic o value of forceps biopsy, cryobiopsy in three seconds, cryobiopsy in five seconds and combined results of cryobiopsy in both timings were recorded. A total of 60 patients (39 males and 21 females; Mean age 56.7 +/- 13.3) were included. Specimens that were obtained by cryobiopsy in five seconds were significantly larger than those of forceps biopsy and cryobiopsy in three seconds (p < 0.001). We showed that the achieved diagnostic yields for all three methods were not statistically different (p > 0.05). Simultaneous usage of samples produced in both cryobiopsies can significantly improve the diagnostic yield (p = 0.02). Statistical analysis showed that there were no significant differences in case of bleeding frequency among the three sampling methods. This study confirmed safety and feasibility of cryobiopsy. Additionally, combination of sampling with two different cold induction timings would significantly increase sensitivity of this emerging technique..

Rediscovering sperm ion channels with the patch-clamp technique

PubMed Central

Kirichok, Yuriy; Lishko, Polina V.

2011-01-01

Upon ejaculation, mammalian spermatozoa have to undergo a sequence of physiological transformations within the female reproductive tract that will allow them to reach and fertilize the egg. These include initiation of motility, hyperactivation of motility and perhaps chemotaxis toward the egg, and culminate in the acrosome reaction that permits sperm to penetrate the protective vestments of the egg. These physiological responses are triggered through the activation of sperm ion channels that cause elevations of sperm intracellular pH and Ca2+ in response to certain cues within the female reproductive tract. Despite their key role in sperm physiology and their absolute requirement for the process of fertilization, sperm ion channels remain poorly understood due to the extreme difficulty in application of the patch-clamp technique to spermatozoa. This review covers the topic of sperm ion channels in the following order: first, we discuss how the intracellular Ca2+ and pH signaling mediated by sperm ion channels controls sperm behavior during the process of fertilization. Then, we briefly cover the history of the methodology to study sperm ion channels, which culminated in the recent development of a reproducible whole-cell patch-clamp technique for mouse and human cells. We further discuss the main approaches used to patch-clamp mature mouse and human spermatozoa. Finally, we focus on the newly discovered sperm ion channels CatSper, KSper (Slo3) and HSper (Hv1), identified by the sperm patch-clamp technique. We conclude that the patch-clamp technique has markedly improved and shifted our understanding of the sperm ion channels, in addition to revealing significant species-specific differences in these channels. This method is critical for identification of the molecular mechanisms that control sperm behavior within the female reproductive tract and make fertilization possible. PMID:21642646

Effects of Imperfect Dynamic Clamp: Computational and Experimental Results

PubMed Central

Bettencourt, Jonathan C.; Lillis, Kyle P.; White, John A.

2008-01-01

In the dynamic clamp technique, a typically nonlinear feedback system delivers electrical current to an excitable cell that represents the actions of “virtual” ion channels (e.g., channels that are gated by local membrane potential or by electrical activity in neighboring biological or virtual neurons). Since the conception of this technique, there have been a number of different implementations of dynamic clamp systems, each with differing levels of flexibility and performance. Embedded hardware-based systems typically offer feedback that is very fast and precisely timed, but these systems are often expensive and sometimes inflexible. PC-based systems, on the other hand, allow the user to write software that defines an arbitrarily complex feedback system, but real-time performance in PC-based systems can be deteriorated by imperfect real-time performance. Here we systematically evaluate the performance requirements for artificial dynamic clamp knock-in of transient sodium and delayed rectifier potassium conductances. Specifically we examine the effects of controller time step duration, differential equation integration method, jitter (variability in time step), and latency (the time lag from reading inputs to updating outputs). Each of these control system flaws is artificially introduced in both simulated and real dynamic clamp experiments. We demonstrate that each of these errors affect dynamic clamp accuracy in a way that depends on the time constants and stiffness of the differential equations being solved. In simulations, time steps above 0.2 ms lead to catastrophic alteration of spike shape, but the frequency-vs.-current relationship is much more robust. Latency (the part of the time step that occurs between measuring membrane potential and injecting re-calculated membrane current) is a crucial factor as well. Experimental data are substantially more sensitive to inaccuracies than simulated data. PMID:18076999

Evaluation of the effect of storage condition on cell extraction and flow cytometric analysis from intestinal biopsies.

PubMed

Wildenberg, Manon E; Duijvestein, Marjolijn; Westera, Liset; van Viegen, Tanja; Buskens, Christianne J; van der Bilt, Jarmila D W; Stitt, Larry; Jairath, Vipul; Feagan, Brian G; Vande Casteele, Niels

2018-06-01

Flow cytometric (FC) analysis of intestinal tissue biopsies requires prompt cell isolation and processing to prevent cell death and generate valid data. We examined the effect of storage conditions prior to cell isolation and FC on viable cell yield and the proportions of immune cell phenotypes from intestinal biopsies. Biopsies (N = 224) from inflamed or non-inflamed ileal and/or colonic tissue from three patients with Crohn's disease were processed and analyzed immediately in duplicate, or stored under different conditions. Cells were isolated and stained for specific markers, followed by FC. Decreased mean live CD45+ cell counts were observed after storage of biopsies at -80 °C dimethyl sulfoxide (DMSO)/citrate buffer compared with immediate processing (1794.3 vs. 19,672.7; p = 0.006]). A non-significant decrease in CD45+ live cell count occurred after storage at -20 °C in DMSO/citrate buffer and cell yield was adequate for subsequent analysis. CD3+ cell proportions were significantly lower after storage at 4 °C in complete medium for 48 h compared with immediate analysis. Mean CD14+ cell proportions were significantly higher after storage of biopsies at -80 °C in DMSO/citrate buffer compared with immediate analysis (2.61% vs. 1.31%, p = 0.007). CD4+, CD8+ and CD4+/CD8+ cell proportions were unaffected by storage condition. Storage of intestinal tissue biopsies at -20 °C in DMSO/citrate buffer for up to 48 h resulted in sufficient viable cell yield for FC analysis without affecting subsequent marker-positive cell proportions. These findings support the potential shipping and storage of intestinal biopsies for centralized FC analysis in multicenter clinical trials. Copyright © 2018 Elsevier B.V. All rights reserved.

Natural Vibration Analysis of Clamped Rectangular Orthotropic Plates

NASA Astrophysics Data System (ADS)

dalaei, m.; kerr, a. d.

The natural vibrations of clamped rectangular orthotropic plates are analyzed using the extended Kantorovich method. The developed iterative scheme converges very rapidly to the final result. The obtained natural frequencies are evaluated for a square plate made of Kevlar 49 Epoxy and the obtained results are compared with those published by Kanazawa and Kawai, and by Leissa. The agreement was found to be very close. As there are no exact analytical solutions for clamped rectangular plates, the generated closed form expression for the natural modes, and the corresponding natural frequencies, are very suitable for use in engineering analyses.

Temporary clamping of external carotid artery in convexity, parasagittal and temporal base meningioma.

PubMed

Yadav, Yad Ram; Parihar, Vijay; Agarwal, Moneet; Bhatele, Pushp Raj

2012-01-01

The management of intraoperative bleeding during removal of a large hyper vascular meningioma is crucial for safe and efficient surgery. Preoperative embolization of meningioma is the best way to reduce vascularity of meningiomas but this technique is not readily available, costly and has its own limitations. The study is aimed to evaluate the use of temporary clamping of external carotid artery to reduce blood loss and operating time during excision of large convexity, parasagittal or temporal base meningiomas. A prospective study of 115 consecutively operated meningiomas of size 5 cms or more were operated from January 2002 to December2010. Temporary clamping of external carotid artery was done in 61 while 51 cases were managed without clamping. There was significant reduction of blood loss, operative time and blood transfusion given in the temporary clipping group compared to non clipping group. There was stitch abscess in two patients each in clamping, and non clamping group. There was no scalp necrosis or mortality in any of the group. Temporary clamping of external carotid artery is a safe, simple and cost-effective alternative to embolization for the surgery of large meningiomas. This can be practiced at all the centers.

Delayed clamping of the umbilical cord after delivery and implications for public cord blood banking.

PubMed

Allan, David S; Scrivens, Nicholas; Lawless, Tiffany; Mostert, Karen; Oppenheimer, Lawrence; Walker, Mark; Petraszko, Tanya; Elmoazzen, Heidi

2016-03-01

Public banking of umbilical cord blood units (CBUs) containing higher numbers of cells ensures timely engraftment after transplantation for increasing numbers of patients. Delayed clamping of the umbilical cord after birth may benefit some infants by preventing iron deficiency. Implications of delayed cord clamping for public cord blood banking remains unclear. CBUs collected by Canadian Blood Services at one collection site between November 1, 2014, and March 17, 2015, were analyzed. The delay in cord clamping after birth was timed and classified as "no delay," 20 to 60 seconds, more than 60 seconds, or more than 120 seconds. Of 367 collections, 100 reported no delay in clamping while clamping was delayed by 20 to 60 seconds (n = 69), more than 60 seconds (n = 98), or more than 120 seconds (n = 100) in the remaining cases. The mean volume and total nucleated cells (TNCs) in units with no delay in clamping were significantly greater than mean volumes for all categories of delayed clamping (Tukey's test, p < 0.05 for each comparison). The proportion of units with more than 1.5 × 10(9) TNCs was significantly reduced when clamping was delayed (p = 5.5 × 10(-8) ). The difference was most marked for cords that were clamped more than 120 seconds after delivery (6.2% compared with 39%). Delayed cord clamping greatly diminishes the volume and TNC count of units collected for a public cord blood bank. Creating an inventory of CBUs with high TNC content may take more time than expected. © 2015 AABB.

[Transthoracic needle-biopsy in coin-lesions of the lung-comparison of the results of different procedures (author's transl)].

PubMed

Dürschmied, H; Polak, J

1980-01-01

This report deals with the results and the complications of transthoracic needle-biopsy performed with different methods at two cooperating hospitals (Prague and Bad Berka). Each hospital investigated 200 persons. As for tumours thin-needle biopsy yielded more positive results for tumours also more false positive results. As for other localized lung diseases the biopsy by means of a Hauser-needle was more successful.

Percutaneous transgastric computed tomography-guided biopsy of the pancreas using large needles

PubMed Central

Tseng, Hsiuo-Shan; Chen, Chia-Yuen; Chan, Wing P; Chiang, Jen-Huey

2009-01-01

AIM: To assess the safety, yield and clinical utility of percutaneous transgastric computed tomography (CT)-guided biopsy of pancreatic tumor using large needles, in selected patients. METHODS: We reviewed 34 CT-guided biopsies in patients with pancreas mass, of whom 24 (71%) had a direct path to the mass without passing through a major organ. The needle passed through the liver in one case (3%). Nine passes (26%) were made through the stomach. These nine transgastric biopsies which used a coaxial technique (i.e. a 17-gauge coaxial introducer needle and an 18-gauge biopsy needle) were the basis of this study. Immediate and late follow-up CT images to detect complications were obtained. RESULTS: Tumor tissues were obtained in nine pancreatic biopsies, and histologic specimens for diagnosis were obtained in all cases. One patient, who had a rare sarcomatoid carcinoma, received a second biopsy. One patient had a complication of transient pneumoperitoneum but no subjective complaints. An immediate imaging study and clinical follow-up detected neither hemorrhage nor peritonitis. No delayed procedure-related complication was seen during the survival period of our patients. CONCLUSION: Pancreatic biopsy can be obtained by a transgastric route using a large needle as an alternative method, without complications of peritonitis or bleeding. PMID:20014462

Preparation of Drosophila central neurons for in situ patch clamping.

PubMed

Ryglewski, Stefanie; Duch, Carsten

2012-10-15

Short generation times and facile genetic techniques make the fruit fly Drosophila melanogaster an excellent genetic model in fundamental neuroscience research. Ion channels are the basis of all behavior since they mediate neuronal excitability. The first voltage gated ion channel cloned was the Drosophila voltage gated potassium channel Shaker(1,2). Toward understanding the role of ion channels and membrane excitability for nervous system function it is useful to combine powerful genetic tools available in Drosophila with in situ patch clamp recordings. For many years such recordings have been hampered by the small size of the Drosophila CNS. Furthermore, a robust sheath made of glia and collagen constituted obstacles for patch pipette access to central neurons. Removal of this sheath is a necessary precondition for patch clamp recordings from any neuron in the adult Drosophila CNS. In recent years scientists have been able to conduct in situ patch clamp recordings from neurons in the adult brain(3,4) and ventral nerve cord of embryonic(5,6), larval(7,8,9,10), and adult Drosophila(11,12,13,14). A stable giga-seal is the main precondition for a good patch and depends on clean contact of the patch pipette with the cell membrane to avoid leak currents. Therefore, for whole cell in situ patch clamp recordings from adult Drosophila neurons must be cleaned thoroughly. In the first step, the ganglionic sheath has to be treated enzymatically and mechanically removed to make the target cells accessible. In the second step, the cell membrane has to be polished so that no layer of glia, collagen or other material may disturb giga-seal formation. This article describes how to prepare an identified central neuron in the Drosophila ventral nerve cord, the flight motoneuron 5 (MN5(15)), for somatic whole cell patch clamp recordings. Identification and visibility of the neuron is achieved by targeted expression of GFP in MN5. We do not aim to explain the patch clamp technique

Dynamic assembly of Hda and the sliding clamp in the regulation of replication licensing

PubMed Central

Kim, Jin S.; Nanfara, Michael T.; Chodavarapu, Sundari; Jin, Kyeong S.; Babu, Vignesh M. P.; Ghazy, Mohamed A.; Chung, Scisung

2017-01-01

Abstract Regulatory inactivation of DnaA (RIDA) is one of the major regulatory mechanisms of prokaryotic replication licensing. In RIDA, the Hda–sliding clamp complex loaded onto DNA directly interacts with adenosine triphosphate (ATP)-bound DnaA and stimulates the hydrolysis of ATP to inactivate DnaA. A prediction is that the activity of Hda is tightly controlled to ensure that replication initiation occurs only once per cell cycle. Here, we determined the crystal structure of the Hda–β clamp complex. This complex contains two pairs of Hda dimers sandwiched between two β clamp rings to form an octamer that is stabilized by three discrete interfaces. Two separate surfaces of Hda make contact with the β clamp, which is essential for Hda function in RIDA. The third interface between Hda monomers occludes the active site arginine finger, blocking its access to DnaA. Taken together, our structural and mutational analyses of the Hda–β clamp complex indicate that the interaction of the β clamp with Hda controls the ability of Hda to interact with DnaA. In the octameric Hda–β clamp complex, the inability of Hda to interact with DnaA is a novel mechanism that may regulate Hda function. PMID:28168278

Accuracy and safety of ultrasound-guided percutaneous needle core biopsy of renal masses

PubMed Central

Wang, Xianding; Lv, Yuanhang; Xu, Zilin; Aniu, Muguo; Qiu, Yang; Wei, Bing; Li, Xiaohong; Wei, Qiang; Dong, Qiang; Lin, Tao

2018-01-01

Abstract Our aim is to determine the sufficiency, accuracy, and safety of ultrasound-guided percutaneous needle core biopsy of renal masses in Chinese patients. Patients who had undergone ultrasound-guided needle core renal mass biopsy from June 2012 to June 2016 at West China Hospital, China were retrospectively reviewed. The information obtained included demographics, mass-related parameters, biopsy indications, technique, complications, pathologic results, and follow-up. Concordance of surgical resection pathology and follow-up data were assessed. Renal mass biopsies were performed in 106 patients. Thirty-nine (36.8%) were asymptomatic. The male/female ratio was 60/46, with a median age of 49.5 years. Median mass size was 8.1 cm (range 1.8–20). Biopsy was performed through a 16-gauge needle, with median cores of 2 taken (range 1–5). Only one significant biopsy-related complication (hemorrhage requiring transfusion) was encountered. An adequate tissue sample was obtained in 97.2% (103/106) of biopsies. Eighty-seven biopsies (82.1%) showed malignant neoplasms, 16 (15.1%) yielded benignity, and 3 (2.8%) were nondiagnostic. After biopsy, 46 patients (43.4%) underwent surgery. Compared with the subsequent mass resection pathology, the biopsy diagnoses were identical in 43 cases. The accuracy rate of biopsy distinguishing malignant from benign lesions was 99.1%, and the rate for determining tumor histological type (excluding the nondiagnostic biopsies) was 95.1%. The sensitivity and specificity in detecting malignancy were 98.9% and 100%, respectively. In several situations, there is still a role for biopsy before intervention. Percutaneous needle core biopsy under ultrasonography guidance is highly accurate and safe, and can determine the proper management of undefinable masses. PMID:29595650

Different methods of hilar clamping during partial nephrectomy: Impact on renal function.

PubMed

Lee, Jeong Woo; Kim, Hwanik; Choo, Minsoo; Park, Yong Hyun; Ku, Ja Hyeon; Kim, Hyeon Hoe; Kwak, Cheol

2014-03-01

To evaluate the impact of different hilar clamping methods on changes in renal function after partial nephrectomy. We analyzed the clinical data of 369 patients who underwent partial nephrectomy for a single renal tumor of size ≤4.0 cm and a normal contralateral kidney. Patients were separated into three groups depending on hilar clamping method: non-clamping, cold ischemia and warm ischemia. Estimated glomerular filtration rate was examined at preoperative, nadir and 1 year postoperatively. Percent change in estimated glomerular filtration rate was used as the parameter to assess the renal functional outcome. Percent change in nadir estimated glomerular filtration rate in the non-clamping group was significantly less compared with the cold ischemia and warm ischemia groups (P < 0.001). However, no significant differences among the groups were noted in percent change of estimated glomerular filtration rate at 1 year (P = 0.348). The cold ischemia group had a similar serial change of postoperative renal function compared with the warm ischemia group. Percent change in 1-year estimated glomerular filtration rate increased with increasing ischemia time in the cold ischemia (P for trend = 0.073) and warm ischemia groups (P for trend = 0.010). On multivariate analysis, hilar clamping (both warm ischemia and cold ischemia) were significantly associated with percent change in nadir estimated glomerular filtration rate, but not in 1-year estimated glomerular filtration rate. Non-clamping partial nephrectomy results in a lower percent change in nadir estimated glomerular filtration rate, whereas it carries an estimated glomerular filtration rate change at 1 year that is similar to partial nephrectomy with cold ischemia and warm ischemia. Cold ischemia and warm ischemia provide a similar effect on renal function. Therefore, when hilar clamping is required, minimization of ischemia time is necessary. © 2013 The Japanese Urological Association.

Implementation of a fast 16-Bit dynamic clamp using LabVIEW-RT.

PubMed

Kullmann, Paul H M; Wheeler, Diek W; Beacom, Joshua; Horn, John P

2004-01-01

The dynamic-clamp method provides a powerful electrophysiological tool for creating virtual ionic conductances in living cells and studying their influence on membrane potential. Here we describe G-clamp, a new way to implement a dynamic clamp using the real-time version of the Lab-VIEW programming environment together with a Windows host, an embedded microprocessor that runs a real-time operating system and a multifunction data-acquisition board. The software includes descriptions of a fast voltage-dependent sodium conductance, delayed rectifier, M-type and A-type potassium conductances, and a leak conductance. The system can also read synaptic conductance waveforms from preassembled data files. These virtual conductances can be reliably implemented at speeds < or =43 kHz while simultaneously saving two channels of data with 16-bit precision. G-clamp also includes utilities for measuring current-voltage relations, synaptic strength, and synaptic gain. Taking an approach built on a commercially available software/hardware platform has resulted in a system that is easy to assemble and upgrade. In addition, the graphical programming structure of LabVIEW should make it relatively easy for others to adapt G-clamp for new experimental applications.

Efficacy of tranexamic acid plus drain-clamping to reduce blood loss in total knee arthroplasty

PubMed Central

Zhang, Yan; Zhang, Jun-Wei; Wang, Bao-Hua

2017-01-01

Abstract Background: Perioperative blood loss is still an unsolved problem in total knee arthroplasty (TKA). The efficacy of the preoperative use of tranexamic acid (TXA) plus drain-clamping to reduce blood loss in TKA has been debated. This meta-analysis aimed to illustrate the efficacy of TXA plus drain-clamping to reduce blood loss in patients who underwent a TKA. Methods: In February 2017, a systematic computer-based search was conducted in PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews, and Google Scholar. Data from patients prepared for TKA in studies that compared TXA plus drain-clamping versus TXA alone, drain-clamping alone, or controls were retrieved. The primary endpoint was the need for transfusion. The secondary outcomes were total blood loss, blood loss in drainage, the decrease in hemoglobin, and the occurrence of deep venous thrombosis. After testing for publication bias and heterogeneity between studies, data were aggregated for random-effects models when necessary. Results: Ultimately, 5 clinical studies with 618 patients (TXA plus drain-clamping group = 249, control group = 130, TXA-alone group = 60, and drain-clamping group = 179) were included. TXA plus drain-clamping could decrease the need for transfusion, total blood loss, blood loss in drainage, and the decrease in hemoglobin than could the control group, the TXA-alone group, and the drain-clamping group (P < .05). There was no significant difference between the occurrence of deep venous thrombosis between the included groups (P > .05). Conclusions: TXA plus drain-clamping can achieve the maximum effects of hemostasis in patients prepared for primary TKA. Because the number and the quality of the included studies were limited, more high-quality randomized controlled trials are needed to identify the optimal dose of TXA and the clamping hours in patients prepared for TKA. PMID:28658157

Rotary powered device for bone marrow aspiration and biopsy yields excellent specimens quickly and efficiently.

PubMed

Swords, Ronan T; Kelly, Kevin R; Cohen, Stephen C; Miller, Larry J; Philbeck, Thomas E; Hacker, Sander O; Spadaccini, Cathy J; Giles, Francis J; Brenner, Andrew J

2010-06-01

Recently, a new FDA-cleared battery powered bone marrow biopsy system was developed to allow operators access to the bone marrow space quickly and efficiently. A pre-clinical evaluation of the device (OnControl, Vidacare Corporation, San Antonio, TX, USA) on anesthetized pigs was conducted, in addition to a clinical evaluation in hematology clinic patients requiring a bone marrow biopsy. Twenty-six samples were collected from the swine model. No cellular artifact or thermal damage was reported in any of the samples obtained. For the clinical evaluation of the device, 16 patients were recruited. Mean time from needle contact with skin to needle removal was 38.5 +/- 13.94 seconds. No complications were reported. In this study, the manual and powered samples were equivalent in specimen quality. In the patients evaluated, the device was safe, easy to use and the mean procedural time was significantly faster than previously reported with a manual technique.

RNA polymerase pausing and nascent RNA structure formation are linked through clamp domain movement

PubMed Central

Hein, Pyae P.; Kolb, Kellie E.; Windgassen, Tricia; Bellecourt, Michael J.; Darst, Seth A.; Mooney, Rachel A.; Landick, Robert

2014-01-01

The rates of RNA synthesis and nascent RNA folding into biologically active structures are linked via pausing by RNA polymerase (RNAP). Structures that form within the RNA exit channel can increase pausing by interacting with bacterial RNAP or decrease pausing by preventing backtracking. Conversely, pausing is required for proper folding of some RNAs. Opening of the RNAP clamp domain is proposed to mediate some effects of nascent RNA structures. However, the connections among RNA structure formation, clamp movement, and catalytic activity remain uncertain. We assayed exit-channel structure formation in Escherichia coli RNAP together with disulfide crosslinks that favor closed or open clamp conformations and found that clamp position directly influences RNA structure formation and catalytic activity. We report that exit-channel RNA structures slow pause escape by favoring clamp opening and through interactions with the flap that slow translocation. PMID:25108353

CT fluoroscopy guided transpleural cutting needle biopsy of small (≤2.5 cm) subpleural pulmonary nodules.

PubMed

Prosch, Helmut; Oschatz, Elisabeth; Eisenhuber, Edith; Wohlschlager, Helmut; Mostbeck, Gerhard H

2011-01-01

Small subpleural pulmonary lesions are difficult to biopsy. While the direct, short needle path has been reported to have a lower rate of pneumothorax, the indirect path provides a higher diagnostic yield. Therefore, we tried to optimize the needle pathway and minimize the iatrogenic pneumothorax risk by evaluating a CT fluoroscopy guided direct approach to biopsy subpleural lesions. Between 01/2005 and 01/2007, CT fluoroscopy guided core biopsies were performed in 24 patients. Using our technique, the tip of the guide needle remains outside the visceral pleura (17 G coaxial guide needle, 18 G Biopsy-gun, 15 or 22 mm needle path). The position of the lesion relative to the needle tip can be optimized using CT fluoroscopy by adjusting the breathing position of the patient. The Biopty gun is fired with the needle tip still outside the pleural space. Cytological smears are analyzed by a cytopathologist on-site, and biopsies are repeated as indicated with the coaxial needle still outside the pleura. Median nodule size was 1.6 cm (0.7-2.3 cm). A definitive diagnosis was obtained in 22 patients by histology and/or cytology. In one patient, only necrotic material could be obtained. In another patient, the intervention had to be aborted as the dyspnoic patient could not follow breathing instructions. An asymptomatic pneumothorax was present in seven patients; chest tube placement was not required. The presented biopsy approach has a high diagnostic yield and is especially advantageous for biopsies of small subpleural lesions in the lower lobes. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Midwives in India: a delayed cord clamping intervention using simulation.

PubMed

Faucher, M A; Riley, C; Prater, L; Reddy, M P

2016-09-01

Iron deficiency is a prevalent health problem in India affecting women and newborns. Delayed umbilical cord clamping at birth is a safe and effective means for increasing serum iron levels in newborns up to 6 months of age. The study aim was to increase the utilization of delayed cord clamping in a group of midwives working in Hyderabad, India. A single group pre- and post-test design was used to evaluate knowledge, beliefs and practice before and after a delayed cord clamping intervention including follow-up at 10 months after the original intervention. The intervention included lectures and simulation. Results show significant increases in knowledge and positive beliefs about the practice of delayed cord clamping. Simulation was effective for eliciting important feedback related to learning. Results represent a small group of midwives working with a non-profit foundation in Southern India. Language discordancy and cultural norms in this group of midwives may have influenced results. Knowledge, beliefs and practice related to delayed cord clamping were all significantly improved after the intervention. The Knowledge to Action framework using simulation is an effective cross-cultural method for implementing education about evidence-based practice. Midwives are invested in learning practices that promote public health. Changing institutional policy may have limitations without first considering normative practice. Using simulation combined with institutional health policy appears to result in significant uptake of practice change. Qualitative studies exploring the interconnections between cultural norms and decision making may be informative about promoting practice change particularly in this setting. Upscaling midwifery has been recommended to improve maternal and child health in India. © 2016 International Council of Nurses.

QPatch: the past, present and future of automated patch clamp.

PubMed

Mathes, Chris

2006-04-01

The QPatch 16 significantly increases throughput for gigaseal patch clamp experiments, making direct measurements in ion channel drug discovery and safety testing feasible. Released to the market in the Autumn of 2004 by Sophion Bioscience, the QPatch originated from work done at NeuroSearch (Denmark) in the early days of automated patch clamp. Today, the QPatch provides many unique features. For example, only the QPatch includes an automated cell preparation station making several hours of unattended operation possible. The 16-channel electrode array, called the QPlate, includes glass-coated microfluidic channels for less compound absorption and, hence, more accurate IC(50) values. The microfluidic pathways also allow for very small amounts of compound used for each experiment ( approximately 5 microl per addition). Only the QPatch has four independent pipetting heads for more efficient liquid handling (especially for ligand-gated ion channel experiments). Patch clamp recordings with the QPatch match the high quality of conventional patch clamp and in some cases the results are even better. For example, only the QPatch includes 100% series resistance compensation for the elimination of false positives due to voltage errors. Finally, the modular QPatch 16 was designed with more channels in mind. The upgrade pathway to 48-channels (the QPatch HT) will be discussed.

Magnetic resonance imaging-guided core needle breast biopsies resulting in high-risk histopathologic findings: upstage frequency and lesion characteristics.

PubMed

Weinfurtner, R Jared; Patel, Bhavika; Laronga, Christine; Lee, Marie C; Falcon, Shannon L; Mooney, Blaise P; Yue, Binglin; Drukteinis, Jennifer S

2015-06-01

Analysis of magnetic resonance imaging-guided breast biopsies yielding high-risk histopathologic features at a single institution found an overall upstage rate to malignancy of 14% at surgical excision. All upstaged lesions were associated with atypical ductal hyperplasia. Flat epithelial atypia and atypical lobular hyperplasia alone or with lobular carcinoma in situ were not associated with an upstage to malignancy. The purpose of the present study w as to determine the malignancy upstage rates and imaging features of high-risk histopathologic findings resulting from magnetic resonance imaging (MRI)-guided core needle breast biopsies. These features include atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), flat epithelial atypia (FEA), and lobular carcinoma in situ (LCIS). A retrospective medical record review was performed on all MRI-guided core needle breast biopsies at a single institution from June 1, 2007 to December 1, 2013 to select biopsies yielding high-risk histopathologic findings. The patient demographics, MRI lesion characteristics, and histopathologic features at biopsy and surgical excision were analyzed. A total of 257 MRI-guided biopsies had been performed, and 50 yielded high-risk histopathologic features (19%). Biopsy site and surgical excision site correlation was confirmed in 29 of 50 cases. Four of 29 lesions (14%) were upstaged: 1 case to invasive ductal carcinoma and 3 cases to ductal carcinoma in situ. ADH alone had an overall upstage rate of 7% (1 of 14), mixed ADH/ALH a rate of 75% (3 of 4), ALH alone or with LCIS a rate of 0% (0 of 7), and FEA a rate of 0% (0 of 4). Only mixed ADH/ALH had a statistically significant upstage rate to malignancy compared with the other high-risk histopathologic subtypes combined. No specific imaging characteristics on MRI were associated with an upstage to malignancy on the statistical analysis. MRI-guided breast biopsies yielding high-risk histopathologic features were associated with

Dynamic assembly of Hda and the sliding clamp in the regulation of replication licensing.

PubMed

Kim, Jin S; Nanfara, Michael T; Chodavarapu, Sundari; Jin, Kyeong S; Babu, Vignesh M P; Ghazy, Mohamed A; Chung, Scisung; Kaguni, Jon M; Sutton, Mark D; Cho, Yunje

2017-04-20

Regulatory inactivation of DnaA (RIDA) is one of the major regulatory mechanisms of prokaryotic replication licensing. In RIDA, the Hda-sliding clamp complex loaded onto DNA directly interacts with adenosine triphosphate (ATP)-bound DnaA and stimulates the hydrolysis of ATP to inactivate DnaA. A prediction is that the activity of Hda is tightly controlled to ensure that replication initiation occurs only once per cell cycle. Here, we determined the crystal structure of the Hda-β clamp complex. This complex contains two pairs of Hda dimers sandwiched between two β clamp rings to form an octamer that is stabilized by three discrete interfaces. Two separate surfaces of Hda make contact with the β clamp, which is essential for Hda function in RIDA. The third interface between Hda monomers occludes the active site arginine finger, blocking its access to DnaA. Taken together, our structural and mutational analyses of the Hda-β clamp complex indicate that the interaction of the β clamp with Hda controls the ability of Hda to interact with DnaA. In the octameric Hda-β clamp complex, the inability of Hda to interact with DnaA is a novel mechanism that may regulate Hda function. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Whole-Cell Electrical Activity Under Direct Mechanical Stimulus by AFM Cantilever Using Planar Patch Clamp Chip Approach

PubMed Central

Upadhye, Kalpesh V.; Candiello, Joseph E.; Davidson, Lance A.; Lin, Hai

2011-01-01

Patch clamp is a powerful tool for studying the properties of ion-channels and cellular membrane. In recent years, planar patch clamp chips have been fabricated from various materials including glass, quartz, silicon, silicon nitride, polydimethyl-siloxane (PDMS), and silicon dioxide. Planar patch clamps have made automation of patch clamp recordings possible. However, most planar patch clamp chips have limitations when used in combination with other techniques. Furthermore, the fabrication methods used are often expensive and require specialized equipments. An improved design as well as fabrication and characterization of a silicon-based planar patch clamp chip are described in this report. Fabrication involves true batch fabrication processes that can be performed in most common microfabrication facilities using well established MEMS techniques. Our planar patch clamp chips can form giga-ohm seals with the cell plasma membrane with success rate comparable to existing patch clamp techniques. The chip permits whole-cell voltage clamp recordings on variety of cell types including Chinese Hamster Ovary (CHO) cells and pheochromocytoma (PC12) cells, for times longer than most available patch clamp chips. When combined with a custom microfluidics chamber, we demonstrate that it is possible to perfuse the extra-cellular as well as intra-cellular buffers. The chamber design allows integration of planar patch clamp with atomic force microscope (AFM). Using our planar patch clamp chip and microfluidics chamber, we have recorded whole-cell mechanosensitive (MS) currents produced by directly stimulating human keratinocyte (HaCaT) cells using an AFM cantilever. Our results reveal the spatial distribution of MS ion channels and temporal details of the responses from MS channels. The results show that planar patch clamp chips have great potential for multi-parametric high throughput studies of ion channel proteins. PMID:22174731

Acoustic plane waves incident on an oblique clamped panel in a rectangular duct

NASA Technical Reports Server (NTRS)

Unz, H.; Roskam, J.

1980-01-01

The theory of acoustic plane waves incident on an oblique clamped panel in a rectangular duct was developed from basic theoretical concepts. The coupling theory between the elastic vibrations of the panel (plate) and the oblique incident acoustic plane wave in infinite space was considered in detail, and was used for the oblique clamped panel in the rectangular duct. The partial differential equation which governs the vibrations of the clamped panel (plate) was modified by adding to it stiffness (spring) forces and damping forces. The Transmission Loss coefficient and the Noise Reduction coefficient for oblique incidence were defined and derived in detail. The resonance frequencies excited by the free vibrations of the oblique finite clamped panel (plate) were derived and calculated in detail for the present case.

Feasibility of Image-Guided Transthoracic Core Needle Biopsy in the BATTLE Lung Trial

PubMed Central

Tam, Alda L.; Kim, Edward S.; Lee, J. Jack; Ensor, Joe E.; Hicks, Marshall E.; Tang, Ximing; Blumenschein, George R.; Alden, Christine M.; Erasmus, Jeremy J.; Tsao, Anne; Lippman, Scott M.; Hong, Waun K.; Wistuba, Ignacio I.; Gupta, Sanjay

2013-01-01

Purpose As therapy for non-small cell lung cancer (NSCLC) patients becomes more personalized, additional tissue in the form of core needle biopsies (CNBs) for biomarker analysis is increasingly required for determining appropriate treatment and for enrollment into clinical trials. We report our experience with small-caliber percutaneous transthoracic (PT) CNBs for the evaluation of multiple molecular biomarkers in BATTLE (Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination), a personalized, targeted therapy NSCLC clinical trial. Methods The medical records of patients who underwent PTCNB for consideration of enrollment in BATTLE, were reviewed for diagnostic yield of 11 predetermined molecular markers, and procedural complications. Univariate and multivariate analyses of factors related to patient and lesion characteristics were performed to determine possible influences on diagnostic yield. Results One hundred and seventy PTCNBs were performed using 20-gauge biopsy needles in 151 NSCLC patients screened for the trial. 82.9% of the biopsy specimens were found to have adequate tumor tissue for analysis of the required biomarkers. On multivariate analysis, metastatic lesions were 5.4 times more likely to yield diagnostic tissue as compared to primary tumors (p = 0.0079). Pneumothorax and chest tube insertion rates were 15.3% and 9.4%, respectively. Conclusions Image-guided 20-gauge PTCNB is safe and provides adequate tissue for analysis of multiple biomarkers in the majority of patients being considered for enrollment into a personalized, targeted therapy NSCLC clinical trial. Metastatic lesions are more likely to yield diagnostic tissue as compared to primary tumors. PMID:23442309

A Contemporary Prostate Biopsy Risk Calculator Based on Multiple Heterogeneous Cohorts.

PubMed

Ankerst, Donna P; Straubinger, Johanna; Selig, Katharina; Guerrios, Lourdes; De Hoedt, Amanda; Hernandez, Javier; Liss, Michael A; Leach, Robin J; Freedland, Stephen J; Kattan, Michael W; Nam, Robert; Haese, Alexander; Montorsi, Francesco; Boorjian, Stephen A; Cooperberg, Matthew R; Poyet, Cedric; Vertosick, Emily; Vickers, Andrew J

2018-05-16

Prostate cancer prediction tools provide quantitative guidance for doctor-patient decision-making regarding biopsy. The widely used online Prostate Cancer Prevention Trial Risk Calculator (PCPTRC) utilized data from the 1990s based on six-core biopsies and outdated grading systems. We prospectively gathered data from men undergoing prostate biopsy in multiple diverse North American and European institutions participating in the Prostate Biopsy Collaborative Group (PBCG) in order to build a state-of-the-art risk prediction tool. We obtained data from 15 611 men undergoing 16 369 prostate biopsies during 2006-2017 at eight North American institutions for model-building and three European institutions for validation. We used multinomial logistic regression to estimate the risks of high-grade prostate cancer (Gleason score ≥7) on biopsy based on clinical characteristics, including age, prostate-specific antigen, digital rectal exam, African ancestry, first-degree family history, and prior negative biopsy. We compared the PBCG model to the PCPTRC using internal cross-validation and external validation on the European cohorts. Cross-validation on the North American cohorts (5992 biopsies) yielded the PBCG model area under the receiver operating characteristic curve (AUC) as 75.5% (95% confidence interval: 74.2-76.8), a small improvement over the AUC of 72.3% (70.9-73.7) for the PCPTRC (p<0.0001). However, calibration and clinical net benefit were far superior for the PBCG model. Using a risk threshold of 10%, clinical use of the PBCG model would lead to the equivalent of 25 fewer biopsies per 1000 patients without missing any high-grade cancers. Results were similar on external validation on 10 377 European biopsies. The PBCG model should be used in place of the PCPTRC for prediction of prostate biopsy outcome. A contemporary risk tool for outcomes on prostate biopsy based on the routine clinical risk factors is now available for informed decision-making. Copyright �

Bone lesion biopsy

MedlinePlus

Bone biopsy; Biopsy - bone ... the cut, then pushed and twisted into the bone. Once the sample is obtained, the needle is ... sample is sent to a lab for examination. Bone biopsy may also be done under general anesthesia ...

Ureteral retrograde brush biopsy

MedlinePlus

Biopsy - brush - urinary tract; Retrograde ureteral brush biopsy cytology; Cytology - ureteral retrograde brush biopsy ... should not be performed in people with a: Urinary tract infection Blockage at or below the biopsy site ...

Open lung biopsy

MedlinePlus

Biopsy - open lung ... An open lung biopsy is done in the hospital using general anesthesia . This means you will be asleep and ... The open lung biopsy is done to evaluate lung problems seen on x-ray or CT scan .

Oropharynx lesion biopsy

MedlinePlus

... Mouth lesion biopsy; Oral cancer - biopsy Images Throat anatomy Oropharyngeal biopsy References Lee FE-H, Treanor JJ. Viral infections. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray & Nadel's Textbook of Respiratory Medicine . 6th ed. Philadelphia, PA: Elsevier ...

Timing of cord clamping in very preterm infants: more evidence is needed.

PubMed

Tarnow-Mordi, William O; Duley, Lelia; Field, David; Marlow, Neil; Morris, Jonathan; Newnham, John; Paneth, Nigel; Soll, Roger F; Sweet, David

2014-08-01

In December 2012, the American College of Obstetricians and Gynecologists published a Committee Opinion entitled "Timing of umbilical cord clamping after birth." It stated that "evidence exists to support delayed cord clamping in preterm infants, when feasible. The single most important benefit for preterm infants is the possibility for a nearly 50% reduction in IVH." However, the Committee Opinion added that the ideal timing of umbilical cord clamping has yet to be determined and recommended that large clinical trials be conducted in the most preterm infants. Published randomized controlled trials include <200 infants of <30 weeks' gestation, with assessments of neurodevelopmental outcome in less than one-half of the children. This is a major gap in the evidence. Without reliable data from randomized controlled trials that optimally include childhood follow-up evaluations, we will not know whether delayed cord clamping may do more overall harm than good. Ongoing trials of delayed cord clamping plan to report childhood outcomes in >2000 additional very preterm infants. Current recommendations may need to change when these results become available. Greater international collaboration could accelerate resolution of whether this promising intervention will improve disability-free survival in about 1 million infants who will be born very preterm globally each year. Copyright © 2014 Mosby, Inc. All rights reserved.

Ion channel drug discovery and research: the automated Nano-Patch-Clamp technology.

PubMed

Brueggemann, A; George, M; Klau, M; Beckler, M; Steindl, J; Behrends, J C; Fertig, N

2004-01-01

Unlike the genomics revolution, which was largely enabled by a single technological advance (high throughput sequencing), rapid advancement in proteomics will require a broader effort to increase the throughput of a number of key tools for functional analysis of different types of proteins. In the case of ion channels -a class of (membrane) proteins of great physiological importance and potential as drug targets- the lack of adequate assay technologies is felt particularly strongly. The available, indirect, high throughput screening methods for ion channels clearly generate insufficient information. The best technology to study ion channel function and screen for compound interaction is the patch clamp technique, but patch clamping suffers from low throughput, which is not acceptable for drug screening. A first step towards a solution is presented here. The nano patch clamp technology, which is based on a planar, microstructured glass chip, enables automatic whole cell patch clamp measurements. The Port-a-Patch is an automated electrophysiology workstation, which uses planar patch clamp chips. This approach enables high quality and high content ion channel and compound evaluation on a one-cell-at-a-time basis. The presented automation of the patch process and its scalability to an array format are the prerequisites for any higher throughput electrophysiology instruments.

Measuring true Young's modulus of a cantilevered nanowire: effect of clamping on resonance frequency.

PubMed

Qin, Qingquan; Xu, Feng; Cao, Yongqing; Ro, Paul I; Zhu, Yong

2012-08-20

The effect of clamping on resonance frequency and thus measured Young's modulus of nanowires (NWs) is systematically investigated via a combined experimental and simulation approach. ZnO NWs are used in this work as an example. The resonance tests are performed in situ inside a scanning electron microscope and the NWs are cantilevered on a tungsten probe by electron-beam-induced deposition (EBID) of hydrocarbon. EBID is repeated several times to deposit more hydrocarbons at the same location. The resonance frequency increases with the increasing clamp size until approaching that under the "fixed" boundary condition. The critical clamp size is identified as a function of NW diameter and NW Young's modulus. This work: 1) exemplifies the importance of considering the effect of clamping in measurements of Young's modulus using the resonance method, and 2) demonstrates that the true Young's modulus can be measured if the critical clamp size is reached. Design guidelines on the critical clamp size are provided. Such design guidelines can be extended to other one-dimensional nanostructures such as carbon nanotubes. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Percutaneous CT-guided biopsy of the spine: results of 430 biopsies

PubMed Central

Rimondi, Eugenio; Errani, Costantino; Bianchi, Giuseppe; Casadei, Roberto; Alberghini, Marco; Malaguti, Maria Cristina; Rossi, Giuseppe; Durante, Stefano; Mercuri, Mario

2008-01-01

Biopsies of lesions in the spine are often challenging procedures with significant risk of complications. CT-guided needle biopsies could lower these risks but uncertainties still exist about the diagnostic accuracy. Aim of this retrospective study was to evaluate the diagnostic accuracy of CT-guided needle biopsies for bone lesions of the spine. We retrieved the results of 430 core needle biopsies carried out over the past fifteen years at the authors’ institute and examined the results obtained. Of the 430 biopsies performed, in 401 cases the right diagnosis was made with the first CT-guided needle biopsy (93.3% accuracy rate). Highest accuracy rates were obtained in primary and secondary malignant lesions. Most false negative results were found in cervical lesions and in benign, pseudotumoral, inflammatory, and systemic pathologies. There were only 9 complications (5 transient paresis, 4 haematomas that resolved spontaneously) that had no influence on the treatment strategy, nor on the patient’s outcome. In conclusion we can assert that this technique is reliable and safe and should be considered the gold standard in biopsies of the spine. PMID:18463900

Bladder biopsy

MedlinePlus

... than usual ( oliguria ). You cannot urinate despite a strong urge to do so. Alternative Names Biopsy - bladder Images Bladder catheterization, female Bladder catheterization, male Female urinary tract Male urinary tract Bladder biopsy ...

Multi-institutional Evaluation of Upper Urinary Tract Biopsy Using Backloaded Cup Biopsy Forceps, a Nitinol Basket, and Standard Cup Biopsy Forceps.

PubMed

Lama, Daniel J; Safiullah, Shoaib; Patel, Roshan M; Lee, Thomas K; Balani, Jyoti P; Zhang, Lishi; Okhunov, Zhamshid; Margulis, Vitaly; Savage, Stephen J; Uchio, Edward; Landman, Jaime

2018-04-06

To compare the performance of 3 contemporary ureteroscopic biopsy devices for the histopathologic diagnosis of upper tract urothelial carcinoma (UTUC). We retrospectively reviewed 145 patients who underwent 182 urothelial biopsies using 2.4F backloaded cup biopsy forceps, a nitinol basket, or 3F standard cup biopsy forceps at 3 tertiary academic centers between 2011 and 2016. Experienced genitourinary pathologists provided an assessment of each specimen without knowledge of the device used for biopsy. For patients who underwent nephroureterectomy without neoadjuvant chemotherapy within 3 months of biopsy-proven UTUC diagnosis, the biopsy grade was compared with both the grade and stage of the surgical specimen. Biopsy utilization varied among the 3 institutions (P <.0001). Significant variabilities in specimen size (P = .001), the presence of intact urothelium (P = .008), and crush artifact (P = .028) were found among the biopsy devices. The quality of specimens from backloaded cup forceps was rated similarly to the nitinol basket (P >.05) and was favored over standard cup forceps specimens. Grade concordance was not affected by specimen size (P >.05), morphology (P >.1), or location (P >.5). No difference existed among the devices in the rate of acquiring a grade concordant biopsy; however, the backloaded cup forceps provided concordant biopsies that could be distinguished as low- and high-grade (P = .02). The backloaded cup forceps and nitinol basket obtained a higher quality urothelial specimen compared with standard cup forceps. Ureteroscopic biopsy device selection did not significantly impact the accuracy of the histologic diagnosis of UTUC. Copyright © 2018 Elsevier Inc. All rights reserved.

A miniaturized planar patch-clamp system for transportable use.

PubMed

Boussaoud, Adrien; Fonteille, Isabelle; Collier, Guilhem; Kermarrec, Frédérique; Vermont, Fabien; Tresallet, Eric; De Waard, Michel; Arnoult, Christophe; Picollet-D'hahan, Nathalie

2012-02-15

In the last decade, planar patch-clamp (PPC) has emerged as an innovative technology allowing parallel recordings of cellular electrophysiological activity on planar substrates. If PPC is widely adopted by the pharmaceutical sector, it remains poorly extended to other areas (i.e. environment and safety organizations) probably because of the large, expensive and non-easily transportable format of those commercial equipments. The present work describes for the first time a new compact and transportable planar patch-clamp system (named Toxint'patch or TIP, for Toxin detection with integrated patch-clamp) focusing on environmental matters and meant to be used in coastal laboratories, for direct on-site monitoring of the seawater and shellfish quality. The TIP system incorporates silicon chips tailored to monitor cellular ionic currents from cultured cells stably expressing a phycotoxin molecular target. The functionality of this novel briefcase-sized PPC system is described in terms of fluidic control, electronic performances with amplifying and filtering boards and of user interface for data acquisition and control implemented on a computer. Copyright © 2011 Elsevier B.V. All rights reserved.

Transjugular Renal Biopsy: Our Experience and Technical Considerations

DOE Office of Scientific and Technical Information (OSTI.GOV)

See, Teik Choon, E-mail: teikchoon.see@addenbrookes.nhs.u; Thompson, Barbara C.; Howie, Alexander J.

2008-09-15

The purpose of this study was to describe the indications for and technique of transjugular renal biopsy (TJRB) and evaluate the efficacy and complications of this method. We performed a retrospective review of 59 patients who underwent TJRB using the Quick-core needle biopsy system (Cook, Letchworth, UK) over a 4-year period. The indications for obtaining renal biopsy included acute renal failure, chronic renal failure, nephrotic syndrome, and proteinuria with or without other associated disease. Indications for the transjugular approach included coagulopathy, biopsy of a solitary kidney or essentially single functioning kidney, simultaneous renal and hepatic biopsy, morbid obesity, and failedmore » percutaneous biopsy. All but four cases were performed via the right internal jugular vein. The right, left, or both renal veins were cannulated in 41, 14, and 4 cases, respectively. Combined liver and renal biopsies were obtained in seven cases. Diagnostic biopsy specimens were obtained in 56 of 59 patients (95%). The number and size of tissue cores ranged from 1 to 9 mm and from 1 to 20 mm, respectively. The mean numbers of glomeruli per procedure on light microscopy and electron microscopy were 10.3 and 2.6, respectively. Specimens for immunohistology were acquired in 49 cases, of which 40 were adequate. Of the 56 successful TJRB procedures, 34 (61%) were associated with isolated capsular perforation (19), contained subcapsular leak (10), isolated collecting system puncture (1), and concurrent collecting system and capsular perforation (4). There was a significant increase in capsular perforation with six or more needle passes, although no significant correlation was seen between number of needle passes and complication. Six patients had minor complications defined as hematuria or loin pain. Seven patients developed major complications, of whom five received blood transfusion alone. Two required intervention: in one an arteriocalyceal fistula was embolized and the

A Comparison of the Performance and Application Differences Between Manual and Automated Patch-Clamp Techniques

PubMed Central

Yajuan, Xiao; Xin, Liang; Zhiyuan, Li

2012-01-01

The patch clamp technique is commonly used in electrophysiological experiments and offers direct insight into ion channel properties through the characterization of ion channel activity. This technique can be used to elucidate the interaction between a drug and a specific ion channel at different conformational states to understand the ion channel modulators’ mechanisms. The patch clamp technique is regarded as a gold standard for ion channel research; however, it suffers from low throughput and high personnel costs. In the last decade, the development of several automated electrophysiology platforms has greatly increased the screen throughput of whole cell electrophysiological recordings. New advancements in the automated patch clamp systems have aimed to provide high data quality, high content, and high throughput. However, due to the limitations noted above, automated patch clamp systems are not capable of replacing manual patch clamp systems in ion channel research. While automated patch clamp systems are useful for screening large amounts of compounds in cell lines that stably express high levels of ion channels, the manual patch clamp technique is still necessary for studying ion channel properties in some research areas and for specific cell types, including primary cells that have mixed cell types and differentiated cells that derive from induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs). Therefore, further improvements in flexibility with regard to cell types and data quality will broaden the applications of the automated patch clamp systems in both academia and industry. PMID:23346269

Conventional forceps or hot biopsy: comparative study of two methods in diagnosis of endobronchial lesions.

PubMed

Jabbari, Hamidreza; Fakhri, Mohammad; Lotfaliani, Mojtaba; Kiani, Arda

2013-01-01

It is suggested that hot electrocoagulation-enabled forceps (hot biopsy) may reduce hemorrhage risk after the biopsy in endobronchial tumors. The main concern in this method is possible reduction of the specimen's quality. To compare the procedure related hemorrhage with hot biopsy and conventional forceps biopsy and the diagnostic quality of the obtained specimens with either technique. In this prospective study, assessment of the biopsy samples and quantity of hemorrhage were done in a blind fashion. At first, for each patient a definite clinical diagnosis was made based on pathologic examination of all available samples, clinical data, and imaging findings. Then, second pathologist reviewed all samples to evaluate the quality of the samples. A total of 36 patients with endobronchial lesions were included in this study. Definite diagnosis was made in 83% of the patients. Diagnostic yield of the two methods were not statistically different, while the mean hemorrhage grades of all hot biopsy protocols were significantly lower as compared to that of conventional biopsy (p=0.003, p<0.001 and p<0.001 for 10,20and40 voltages respectively). No significant difference was detected between the qualities of specimens obtained by hot biopsy methods in comparison with conventional biopsy (p>0.05 for all three voltages). Hot biopsy can be a valuable alternative to forceps biopsy in evaluating endobronchial lesions.

[Advantage of delayed umbilical cord clamping in the newborn infant].

PubMed

Menget, A; Mougey, C; Thiriez, G; Riethmuller, D

2013-09-01

The timing of umbilical cord clamping remains controversial. Although most maternity wards use the early clamping (5-15s), randomized studies and meta-analyses have demonstrated the benefit of delayed clamping for term and preterm newborn infants over the past 10 years. Indeed, placentofetal transfusion of 20-30 ml/kg in 2-3 min improves the iron status of term infants and prevents infant hypochromic anemia. Infant anemia is a public health problem in many developing countries. For preterm newborns, placental transfusion for 45 s or milking the cord for 15 s improves cardiovascular adaptation, with better hemodynamic stability, as well as decreased intraventricular hemorrhages, need for transfusion, and late-onset sepsis. A new look at this symbolic act is needed and professionals need to be persuaded of the importance of the "wait a minute" policy for a better physiological delivery. Copyright © 2013. Published by Elsevier SAS.

CT-Guided Biopsy of Small Liver Lesions: Visibility, Artifacts, and Corresponding Diagnostic Accuracy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stattaus, Joerg, E-mail: joerg.stattaus@uni-due.de; Kuehl, Hilmar; Ladd, Susanne

2007-09-15

Purpose. Our study aimed to determine the visibility of small liver lesions during CT-guided biopsy and to assess the influence of lesion visibility on biopsy results. Material and Methods. Fifty patients underwent CT-guided core biopsy of small focal liver lesions (maximum diameter, 3 cm); 38 biopsies were performed using noncontrast CT, and the remaining 12 were contrast-enhanced. Visibility of all lesions was graded on a 4-point-scale (0 = not visible, 1 = poorly visible, 2 = sufficiently visible, 3 = excellently visible) before and during biopsy (with the needle placed adjacent to and within the target lesion). Results. Forty-three biopsiesmore » (86%) yielded diagnostic results, and seven biopsies were false-negative. In noncontrast biopsies, the rate of insufficiently visualized lesions (grades 0-1) increased significantly during the procedure, from 10.5% to 44.7%, due to needle artifacts. This resulted in more (17.6%) false-negative biopsy results compared to lesions with good visualization (4.8%), although this difference lacks statistical significance. Visualization impairment appeared more often with an intercostal or subcostal vs. an epigastric access and with a subcapsular vs. a central lesion location, respectively. With contrast-enhanced biopsy the visibility of hepatic lesions was only temporarily improved, with a risk of complete obscuration in the late phase. Conclusion. In conclusion, visibility of small liver lesions diminished significantly during CT-guided biopsy due to needle artifacts, with a fourfold increased rate of insufficiently visualized lesions and of false-negative histological results. Contrast enhancement did not reveal better results.« less

Trans-rectal ultrasound visibility of prostate lesions identified by magnetic resonance imaging increases accuracy of image-fusion targeted biopsies.

PubMed

Ukimura, Osamu; Marien, Arnaud; Palmer, Suzanne; Villers, Arnauld; Aron, Manju; de Castro Abreu, Andre Luis; Leslie, Scott; Shoji, Sunao; Matsugasumi, Toru; Gross, Mitchell; Dasgupta, Prokar; Gill, Inderbir S

2015-11-01

To compare the diagnostic yield of targeted prostate biopsy using image-fusion of multi-parametric magnetic resonance (mp-MR) with real-time trans-rectal ultrasound (TRUS) for clinically significant lesions that are suspicious only on mp-MR versus lesions that are suspicious on both mp-MR and TRUS. Pre-biopsy MRI and TRUS were each scaled on a 3-point score: highly suspicious, likely, and unlikely for clinically significant cancer (sPCa). Using an MR-TRUS elastic image-fusion system (Koelis), a 127 consecutive patients with a suspicious clinically significant index lesion on pre-biopsy mp-MR underwent systematic biopsies and MR/US-fusion targeted biopsies (01/2010-09/2013). Biopsy histological outcomes were retrospectively compared with MR suspicion level and TRUS-visibility of the MR-suspicious lesion. sPCa was defined as biopsy Gleason score ≥7 and/or maximum cancer core length ≥5 mm. Targeted biopsies outperformed systematic biopsies in overall cancer detection rate (61 vs. 41 %; p = 0.007), sPCa detection rate (43 vs. 23 %; p = 0.0013), cancer core length (7.5 vs. 3.9 mm; p = 0.0002), and cancer rate per core (56 vs. 12 %; p < 0.0001), respectively. Highly suspicious lesions on mp-MR correlated with higher positive biopsy rate (p < 0.0001), higher Gleason score (p = 0.018), and greater cancer core length (p < 0.0001). Highly suspicious lesions on TRUS in corresponding to MR-suspicious lesion had a higher biopsy yield (p < 0.0001) and higher sPCa detection rate (p < 0.0001). Since majority of MR-suspicious lesions were also suspicious on TRUS, TRUS-visibility allowed selection of the specific MR-visible lesion which should be targeted from among the multiple TRUS suspicious lesions in each prostate. MR-TRUS fusion-image-guided biopsies outperformed systematic biopsies. TRUS-visibility of a MR-suspicious lesion facilitates image-guided biopsies, resulting in higher detection of significant cancer.

An isolated Hda-clamp complex is functional in the regulatory inactivation of DnaA and DNA replication.

PubMed

Kawakami, Hironori; Su'etsugu, Masayuki; Katayama, Tsutomu

2006-10-01

In Escherichia coli, a complex consisting of Hda and the DNA-loaded clamp-subunit of the DNA polymerase III holoenzyme promotes hydrolysis of DnaA-ATP. The resultant ADP-DnaA is inactive for initiation of chromosomal DNA replication, thereby repressing excessive initiations. As the cellular content of the clamp is 10-100 times higher than that of Hda, most Hda molecules might be complexed with the clamp in vivo. Although Hda predominantly forms irregular aggregates when overexpressed, in the present study we found that co-overexpression of the clamp with Hda enhances Hda solubility dramatically and we efficiently isolated the Hda-clamp complex. A single molecule of the complex appears to consist of two Hda molecules and a single clamp. The complex is competent in DnaA-ATP hydrolysis and DNA replication in the presence of DNA and the clamp deficient subassembly of the DNA polymerase III holoenzyme (pol III*). These findings indicate that the clamp contained in the complex is loaded onto DNA through an interaction with the pol III* and that the Hda activity is preserved in these processes. The complex consisting of Hda and the DNA-unloaded clamp may play a specific role in a process proceeding to the DnaA-ATP hydrolysis in vivo.

Vortex-dislodged cells from bone marrow trephine biopsy yield satisfactory results for flow cytometric immunophenotyping.

PubMed

Bommannan, K; Sachdeva, M U S; Gupta, M; Bose, P; Kumar, N; Sharma, P; Naseem, S; Ahluwalia, J; Das, R; Varma, N

2016-10-01

A good bone marrow (BM) sample is essential in evaluating many hematologic disorders. An unsuccessful BM aspiration (BMA) procedure precludes a successful flow cytometric immunophenotyping (FCI) in most hematologic malignancies. Apart from FCI, most ancillary diagnostic techniques in hematology are less informative. We describe the feasibility of FCI in vortex-dislodged cell preparation obtained from unfixed trephine biopsy (TB) specimens. In pancytopenic patients and dry tap cases, routine diagnostic BMA and TB samples were complemented by additional trephine biopsies. These supplementary cores were immediately transferred into sterile tubes filled with phosphate-buffered saline, vortexed, and centrifuged. The cell pellet obtained was used for flow cytometric immunophenotyping. Of 7955 BMAs performed in 42 months, 34 dry tap cases were eligible for the study. Vortexing rendered a cell pellet in 94% of the cases (32 of 34), and FCI rendered a rapid diagnosis in 100% of the cases (32 of 32) where cell pellets were available. We describe an efficient procedure which could be effectively utilized in resource-limited centers and reduce the frequency of repeat BMA procedures. © 2016 John Wiley & Sons Ltd.

The Nano-Patch-Clamp Array: Microfabricated Glass Chips for High-Throughput Electrophysiology

NASA Astrophysics Data System (ADS)

Fertig, Niels

2003-03-01

Electrophysiology (i.e. patch clamping) remains the gold standard for pharmacological testing of putative ion channel active drugs (ICADs), but suffers from low throughput. A new ion channel screening technology based on microfabricated glass chip devices will be presented. The glass chips contain very fine apertures, which are used for whole-cell voltage clamp recordings as well as single channel recordings from mammalian cell lines. Chips containing multiple patch clamp wells will be used in a first bench-top device, which will allow perfusion and electrical readout of each well. This scalable technology will allow for automated, rapid and parallel screening on ion channel drug targets.

Laser-assisted patch clamping: a methodology

NASA Technical Reports Server (NTRS)

Henriksen, G. H.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

1997-01-01

Laser microsurgery can be used to perform both cell biological manipulations, such as targeted cell ablation, and molecular genetic manipulations, such as genetic transformation and chromosome dissection. In this report, we describe a laser microsurgical method that can be used either to ablate single cells or to ablate a small area (1-3 microns diameter) of the extracellular matrix. In plants and microorganisms, the extracellular matrix consists of the cell wall. While conventional patch clamping of these cells, as well as of many animal cells, requires enzymatic digestion of the extracellular matrix, we illustrate that laser microsurgery of a portion of the wall enables patch clamp access to the plasma membrane of higher plant cells remaining situated in their tissue environment. What follows is a detailed description of the construction and use of an economical laser microsurgery system, including procedures for single cell and targeted cell wall ablation. This methodology will be of interest to scientists wishing to perform cellular or subcellular ablation with a high degree of accuracy, or wishing to study how the extracellular matrix affects ion channel function.

A novel monolithic piezoelectric actuated flexure-mechanism based wire clamp for microelectronic device packaging.

PubMed

Liang, Cunman; Wang, Fujun; Tian, Yanling; Zhao, Xingyu; Zhang, Hongjie; Cui, Liangyu; Zhang, Dawei; Ferreira, Placid

2015-04-01

A novel monolithic piezoelectric actuated wire clamp is presented in this paper to achieve fast, accurate, and robust microelectronic device packaging. The wire clamp has compact, flexure-based mechanical structure and light weight. To obtain large and robust jaw displacements and ensure parallel jaw grasping, a two-stage amplification composed of a homothetic bridge type mechanism and a parallelogram leverage mechanism was designed. Pseudo-rigid-body model and Lagrange approaches were employed to conduct the kinematic, static, and dynamic modeling of the wire clamp and optimization design was carried out. The displacement amplification ratio, maximum allowable stress, and natural frequency were calculated. Finite element analysis (FEA) was conducted to evaluate the characteristics of the wire clamp and wire electro discharge machining technique was utilized to fabricate the monolithic structure. Experimental tests were carried out to investigate the performance and the experimental results match well with the theoretical calculation and FEA. The amplification ratio of the clamp is 20.96 and the working mode frequency is 895 Hz. Step response test shows that the wire clamp has fast response and high accuracy and the motion resolution is 0.2 μm. High speed precision grasping operations of gold and copper wires were realized using the wire clamper.

HTS techniques for patch clamp-based ion channel screening - advances and economy.

PubMed

Farre, Cecilia; Fertig, Niels

2012-06-01

Ten years ago, the first publication appeared showing patch clamp recordings performed on a planar glass chip instead of using a conventional patch clamp pipette. "Going planar" proved to revolutionize ion channel drug screening as we know it, by allowing high quality measurements of ion channels and their effectors at a higher throughput and at the same time de-skilling the highly laborious technique. Over the years, platforms evolved in response to user requirements regarding experimental features, data handling plus storage, and suitable target diversity. This article gives a snapshot image of patch clamp-based ion channel screening with focus on platforms developed to meet requirements of high-throughput screening environments. The commercially available platforms are described, along with their benefits and drawbacks in ion channel drug screening. Automated patch clamp (APC) platforms allow faster investigation of a larger number of ion channel active compounds or cell clones than previously possible. Since patch clamp is the only method allowing direct, real-time measurements of ion channel activity, APC holds the promise of picking up high quality leads, where they otherwise would have been overseen using indirect methods. In addition, drug candidate safety profiling can be performed earlier in the drug discovery process, avoiding late-phase compound withdrawal due to safety liability issues, which is highly costly and inefficient.

Core Needle Lung Biopsy Specimens: Adequacy for EGFR and KRAS Mutational Analysis

PubMed Central

Zakowski, Maureen F.; Pao, William; Thornton, Raymond H.; Ladanyi, Marc; Kris, Mark G.; Rusch, Valerie W.; Rizvi, Naiyer A.

2013-01-01

OBJECTIVE The purpose of this study was to prospectively compare the adequacy of core needle biopsy specimens with the adequacy of specimens from resected tissue, the histologic reference standard, for mutational analysis of malignant tumors of the lung. SUBJECTS AND METHODS The first 18 patients enrolled in a phase 2 study of gefitinib for lung cancer in July 2004 through August 2005 underwent CT- or fluoroscopy-guided lung biopsy before the start of gefitinib therapy. Three weeks after gefitinib therapy, the patients underwent lung tumor resection. The results of EGFR and KRAS mutational analysis of the core needle biopsy specimens were compared with those of EGFR and KRAS mutational analysis of the surgical specimens. RESULTS Two specimens were unsatisfactory for mutational analysis. The results of mutational assay results of the other 16 specimens were the same as those of analysis of the surgical specimens obtained an average of 31 days after biopsy. CONCLUSION Biopsy with small (18- to 20-gauge) core needles can yield sufficient and reliable samples for mutational analysis. This technique is likely to become an important tool with the increasing use of pharmacotherapy based on the genetics of specific tumors in individual patients. PMID:20028932

Automated and manual patch clamp data of human induced pluripotent stem cell-derived dopaminergic neurons.

PubMed

Franz, Denise; Olsen, Hervør Lykke; Klink, Oliver; Gimsa, Jan

2017-04-25

Human induced pluripotent stem cells can be differentiated into dopaminergic neurons (Dopa.4U). Dopa.4U neurons expressed voltage-gated Na V and K V channels and showed neuron-like spontaneous electrical activity. In automated patch clamp measurements with suspended Dopa.4U neurons, delayed rectifier K + current (delayed K V ) and rapidly inactivating A-type K + current (fast K V ) were identified. Examination of the fast K V current with inhibitors yielded IC 50 values of 0.4 mM (4-aminopyridine) and 0.1 mM (tetraethylammonium). In manual patch clamp measurements with adherent Dopa.4U neurons, fast K V current could not be detected, while the delayed K V current showed an IC 50 of 2 mM for 4-aminopyridine. The Na V channels in adherent and suspended Dopa.4U neurons showed IC 50 values for tetrodotoxin of 27 and 2.9 nM, respectively. GABA-induced currents that could be observed in adherent Dopa.4U neurons could not be detected in suspended cells. Application of current pulses induced action potentials in approx. 70 % of the cells. Our results proved the feasibility of automated electrophysiological characterization of neuronal cells.

Diagnosis of small pulmonary lesions by transbronchial lung biopsy with radial endobronchial ultrasound and virtual bronchoscopic navigation versus CT-guided transthoracic needle biopsy: A systematic review and meta-analysis

PubMed Central

Han, Yeji; Kim, Hyun Jung; Kong, Kyoung Ae; Kim, Soo Jung; Lee, Su Hwan; Ryu, Yon Ju; Lee, Jin Hwa; Kim, Yookyoung; Shim, Sung Shine

2018-01-01

Background Advances in bronchoscopy and CT-guided lung biopsy have improved the evaluation of small pulmonary lesions (PLs), leading to an increase in preoperative histological diagnosis. We aimed to evaluate the efficacy and safety of transbronchial lung biopsy using radial endobronchial ultrasound and virtual bronchoscopic navigation (TBLB-rEBUS&VBN) and CT-guided transthoracic needle biopsy (CT-TNB) for tissue diagnosis of small PLs. Methods A systematic search was performed in five electronic databases, including MEDLINE, EMBASE, Cochrane Library Central Register of Controlled Trials, Web of Science, and Scopus, for relevant studies in May 2016; the selected articles were assessed using meta-analysis. The articles were limited to those published after 2000 that studied small PLs ≤ 3 cm in diameter. Results From 7345 records, 9 articles on the bronchoscopic (BR) approach and 15 articles on the percutaneous (PC) approach were selected. The pooled diagnostic yield was 75% (95% confidence interval [CI], 69–80) using the BR approach and 93% (95% CI, 90–96) using the PC approach. For PLs ≤ 2 cm, the PC approach (pooled diagnostic yield: 92%, 95% CI: 88–95) was superior to the BR approach (66%, 95% CI: 55–76). However, for PLs > 2 cm but ≤ 3 cm, the diagnostic yield using the BR approach was improved to 81% (95% CI, 75–85). Complications of pneumothorax and hemorrhage were rare with the BR approach but common with the PC approach. Conclusions CT-TNB was superior to TBLB-rEBUS&VBN for the evaluation of small PLs. However, for lesions greater than 2 cm, the BR approach may be considered considering its diagnostic yield of over 80% and the low risk of procedure-related complications. PMID:29357388

Efficacy of deep biopsy for subepithelial lesions in the upper gastrointestinal tract.

PubMed

Vaicekauskas, Rolandas; Stanaitis, Juozas; Valantinas, Jonas

2016-01-01

Accurate diagnosis of subepithelial lesions (SELs) in the gastrointestinal tract depends on a variety of methods: endoscopy, endoscopic ultrasound and different types of biopsy. Making an error-free diagnosis is vital for the subsequent application of an appropriate treatment. To evaluate the efficacy of deep biopsy via the endoscopic submucosal dissection (ESD) technique for SELs in the upper gastrointestinal tract. It was a case series study. Deep biopsy via the ESD technique was completed in 38 patients between November 2012 and October 2014. Thirty-eight SELs in the upper gastrointestinal tract of varying size (very small ≤ 1 cm, small 1-2 cm and large ≥ 2 cm) by means of the ESD technique after an incision with an electrosurgical knife of the overlying layers and revealing a small part of the lesion were biopsied under direct endoscopic view. Deep biopsy via the ESD technique was diagnostic in 28 of 38 patients (73.3%; 95% CI: 59.7-89.7%). The diagnostic yield for SELs with a clear endophytic shape increased to 91.3%. An evident endophytic appearance of a subepithelial lesion, the mean number of biopsied samples (6.65 ±1.36) and the total size in length of all samples per case (19.88 ±8.07 mm) were the main criteria influencing the positiveness of deep biopsy in the diagnostic group compared to the nondiagnostic one (p = 0.001; p = 0.025; p = 0.008). Deep biopsy via the ESD technique is an effective and safe method for the diagnosis of SELs especially with a clear endophytic appearance in a large number of biopsied samples.

Radial scars without atypia in percutaneous biopsy specimens: can they obviate surgical biopsy?

PubMed

Mesa-Quesada, J; Romero-Martín, S; Cara-García, M; Martínez-López, A; Medina-Pérez, M; Raya-Povedano, J L

To evaluate the need for surgical biopsy in patients diagnosed with radial scars without atypia by percutaneous biopsy. In this retrospective observational study, we selected patients with a histological diagnosis of radial scar in specimens obtained by percutaneous biopsy during an 8-year period. The statistical analysis was centered on patients with radial scar without atypia (we assessed the radiologic presentation, the results of the percutaneous biopsy, and their correlation with the results of surgical biopsy and follow-up) and we added the patients with atypia and cancer in the elaboration of the diagnostic indices. We identified 96 patients with radial scar on percutaneous biopsy; 54 had no atypia, 18 had atypia, and 24 had cancer. Among patients with radial scar without atypia, there were no statistically significant differences between patients who underwent imaging follow-up and those who underwent surgical biopsy (p>0.05). The rate of underdiagnosis for percutaneous biopsy in patients without atypia was 1.9%. The rates of diagnosis obtained with percutaneous biopsy in relation to follow-up and surgical biopsy in the 96 cases were sensitivity 92.3%, specificity 100%, positive predictive value 100%, negative predictive value 97.2%, and accuracy 97.9%. The area under the ROC curve was 0.96 (p<0.001), and the kappa concordance index was 0.95 (p<0.001) CONCLUSIONS: We consider that it is not necessary to perform surgical biopsies in patients with radial scars without atypia on percutaneous biopsies because the rate of underestimation is very low and the concordance between the diagnosis reached by percutaneous biopsy and the definitive diagnosis is very high. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

The best prostate biopsy scheme is dictated by the gland volume: a monocentric study.

PubMed

Dell'Atti, L

2015-08-01

Accuracy of biopsy scheme depends on different parameters. Prostate-specific antigen (PSA) level and digital rectal examination (DRE) influenced the detection rate and suggested the biopsy scheme to approach each patient. Another parameter is the prostate volume. Sampling accuracy tends to decrease progressively with an increasing prostate volume. We prospectively observed detection cancer rate in suspicious prostate cancer (PCa) and improved by applying a protocol biopsy according to prostate volume (PV). Clinical data and pathological features of these 1356 patients were analysed and included in this study. This protocol is a combined scheme that includes transrectal (TR) 12-core PBx (TR12PBx) for PV ≤ 30 cc, TR 14-core PBx (TR14PBx) for PV > 30 cc but < 60 cc, TR 18-core PBx (TR18PBx) for PV ≥ 60 cc. Out of a total of 1356 patients, in 111 (8.2%) PCa was identified through TR12PBx scheme, in 198 (14.6%) through TR14PBx scheme and in 253 (18.6%) through TR18PBx scheme. The PCa detection rate was increased by 44% by adding two TZ cores (TR14PBx scheme). The TR18PBx scheme increased this rate by 21.7% vs. TR14PBx scheme. The diagnostic yield offered by TR18PBx was statistically significant compared to the detection rate offered by the TR14PBx scheme (p < 0.003). The biopsy Gleason score and the percentage of core involvement were comparable between PCa detected by the TR14PBx scheme diagnostic yield and those detected by the TR18PBx scheme (p = 0.362). The only PV parameter, in our opinion, can be significant in choosing the best biopsy scheme to approach in a first setting of biopsies increasing PCa detection rate.

Tensile film clamps and mounting block for the rheovibron and autovibron viscoelastometer

NASA Technical Reports Server (NTRS)

Stoakley, Diane M. (Inventor); St.clair, Anne K. (Inventor); Little, Bruce D. (Inventor)

1989-01-01

A set of film clamps and a mounting block for use in the determination of tensile modulus and damping properties of films in a manually operated or automated Rheovibron is diagrammed. These clamps and mounting block provide uniformity of sample gripping and alignment in the instrument. Operator dependence and data variability are greatly reduced.

Testicular biopsy

MedlinePlus

... Names Biopsy - testicle Images Endocrine glands Male reproductive anatomy Testicular biopsy References Garibaldi LR, Chematilly W. Disorders of pubertal development. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, PA: Elsevier; 2016: ...

[Identification of hepatitis B virus YMDD point mutation using peptide nucleic acid clamping PCR].

PubMed

Zhang, Yingying; He, Haitang; Yang, Jie; Hou, Jinlin

2013-06-01

To establish a peptide nucleic acid clamping PCR assay for detecting hepatitis B virus (HBV) drug resistance mutation. RtM204I (ATT) mutant, rtM204V (GTG) mutant and rtM204 (ATG) wild-type plasmids mixed at different ratios were detected for mutations by PNA clamping PCR assay and direct sequencing, and the sensitivity and specificity of the two methods were compared. Serum samples from 85 patients with chronic HBV infection were detected for drug resistance using the two methods. The sensitivity of PNA-PCR assay was 0.001% in a 10(5)-fold excess of wild-type HBV DNA with a detection limit of 10(1) copies. The sensitivity of direct sequencing was 10% with a detection limit of 10(4) copies. Mutants were detected in 73 of the 85 serum samples (85.9%), including YIDD in 40 samples, YVDD in 23 samples, and YIDD+YVDD in 10 samples. The agreement of PNA-PCR assay with direct sequencing was only 40% (34/85, YIDD in 21 samples, YVDD in 11 samples, and YIDD+YVDD in 2 samples). Neither of the two methods yielded positive results for the negative control samples, suggesting their good specificity. PNA-PCR assay appears to be a more sensitive and rapid assay for detection of HBV genotypic resistance.

Influence of clamp-up force on the strength of bolted composite joints

NASA Astrophysics Data System (ADS)

Horn, Walter J.; Schmitt, Ron R.

1994-03-01

Composite materials offer the potential for a reduction in the number of individual parts and joints in a structure because large one-piece components can replace multipart assemblies. Nevertheless, there are many situations where composite parts must be joined and often mechanical fasteners provide the only practical method of joining those parts. The long-term strength of mechanically fastened joints of composite members can be directly affected by the clamp-up force of the fastener and thus perhaps by the relaxation of this force due to the viscoelastic character of the composite materials of the joint. Methods for predicting the effect of bolt clamp-up force relaxation on the strength of mechanically fastened joints of thermoplastic composite materials were investigated during the present study. A test program, using two thermoplastic composite materials, was conducted to determine the influence of clamp-up force on joint strength, to measure the relaxation of the joint clamp-up force with time, and to measure the change of joint strength as a function of time.

33 CFR 183.560 - Hose clamps: Installation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Hose clamps: Installation. 183.560 Section 183.560 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Manufacturer Requirements § 183.560...

Clamp and Gas Nozzle for TIG Welding

NASA Technical Reports Server (NTRS)

Gue, G. B.; Goller, H. L.

1982-01-01

Tool that combines clamp with gas nozzle is aid to tungsten/inert-gas (TIG) welding in hard-to-reach spots. Tool holds work to be welded while directing a stream of argon gas at weld joint, providing an oxygen-free environment for tungsten-arc welding.

Electrophysiological/sonographic mapping of the superficial peroneal nerve to facilitate biopsy under local anaesthesia.

PubMed

Tudose, Andrei; Hogg, Florence R A; Bland, Jeremy D P; Walsh, Daniel C

2017-04-01

The anatomical surface markings for the superficial peroneal nerve have been described and it may be preferred for biopsy in cases of suspected vasculitis as biopsy of the peroneus brevis muscle increases diagnostic yield. The procedure is however unfamiliar to many surgeons and the anatomical variability of the subcutaneous part underestimated. Where the nerve has some preserved sensory nerve action potential it may be mapped pre-operatively, greatly facilitating minimally traumatic biopsy with potential logistical and wound healing advantages. We review the literature relating to the anatomical course of the nerve and present a case illustrating the advantages of pre-operative mapping, given its location in the anterior compartment of the leg 26% of the time.

Transbronchial biopsy in the management of pulmonary complications of hematopoietic stem cell transplantation

PubMed Central

O’Dwyer, David N.; Duvall, Adam S.; Xia, Meng; Hoffman, Timothy C.; Bloye, Kiernan S.; Bulte, Camille A.; Zhou, Xiaofeng; Murray, Susan; Moore, Bethany B.; Yanik, Gregory A.

2017-01-01

The utility of transbronchial biopsy in the management of pulmonary complications following hematopoietic stem cell transplantation has shown variable results. Herein, we examine the largest case series of patients undergoing transbronchial biopsy following hematopoietic stem cell transplantation. We performed a retrospective analysis of 130 transbronchial biopsy cases performed in patients with pulmonary complications post-hematopoietic stem cell transplantation. Logistic regression models were applied to examine diagnostic yield, odds of therapy change and complications. The most common histologic finding on transbronchial biopsy was a non-specific interstitial pneumonitis (n= 24 cases, 18%). Pathogens identified by transbronchial biopsy were rare, occurring in < 5% of cases. A positive transbronchial biopsy significantly increased the odds of a subsequent change in corticosteroid therapy (OR=3.12, 95% CI 1.18–8.23; p=0.02) but was not associated with a change in antibiotic therapy (OR=1.01, 95% CI 0.40–2.54; p=0.98) or changes in overall therapy (OR=1.92, 95% CI 0.79–4.70; p=0.15). Patients who underwent a transbronchial biopsy had increased odds of complications related to the bronchoscopy (OR=3.33, 95% CI 1.63–6.79; p=0.001). In conclusion, transbronchial biopsy may contribute to the diagnostic management of non-infectious lung injury post-hematopoietic stem cell transplantation, while its utility in the management of infectious pulmonary complications of HSCT remains low. PMID:29058699

Hemiarch Reconstruction Vs Clamped Aortic Anastomosis for Concomitant Ascending Aortic Aneurysm.

PubMed

Sultan, Ibrahim; Bianco, Valentino; Yajzi, Ibrahim; Kilic, Arman; Dufendach, Keith; Cardounel, Arturo; Althouse, Andrew D; Masri, Ahmad; Navid, Forozan; Gleason, Thomas G

2018-05-03

Deep hypothermic circulatory arrest (DHCA) is often avoided in patients with concomitant ascending aortic pathology when treating other cardiac disease to avoid increased risk of morbidity and mortality. We hypothesized that the use of DHCA with retrograde cerebral perfusion (RCP) does not add incremental risk to ascending aortic replacement alone in the setting of concomitant cardiac surgery. 408 ascending aortic ± hemiarch replacements and aortic (root)/mitral/tricuspid valve(s), CABG, or MAZE procedures were performed for concomitant cardiac disease. DHCA with RCP was used for all hemiarch replacements or the ascending aorta was replaced with an aortic cross-clamp proximal to the innominate artery. Propensity-score matching was used to match similar ascending patients vs. hemiarch patients; the final propensity score matched patients on age, gender, BMI, previous heart surgery, pre-op aortic insufficiency, pre-op aortic stenosis, pre-op EF, and operative variables. Propensity-score matching yielded 116 pairs of Non-hemiarch patients vs. 116 hemiarch patients. Within the propensity-score matched cohort, there were no differences in postoperative stroke (1.7% vs. 3.4%, p = 0.41), new postoperative dialysis (6.0% vs. 5.2%, p = 0.78), postoperative renal insufficiency (27.6% vs. 19.8%, p = 0.16), 30-day mortality (2.6% vs. 3.4%, p = 0.701), or 1-year mortality (4.3% vs. 4.3%, p = 1.00) CONCLUSIONS: Hemiarch replacement using DHCA with RCP does not increase the risk of operative complications compared to a normothermic, clamped-distal aortic anastomosis, and therefore its use should not be limited when planning complex multi-procedural reconstructions during elective ascending thoracic aortic replacement with concomitant cardiac surgery. Copyright © 2018. Published by Elsevier Inc.

EBUS-TBNA Provides Highest RNA Yield for Multiple Biomarker Testing from Routinely Obtained Small Biopsies in Non-Small Cell Lung Cancer Patients - A Comparative Study of Three Different Minimal Invasive Sampling Methods

PubMed Central

Schmid-Bindert, Gerald; Wang, Yongsheng; Jiang, Hongbin; Sun, Hui; Henzler, Thomas; Wang, Hao; Pilz, Lothar R.; Ren, Shengxiang; Zhou, Caicun

2013-01-01

Background Multiple biomarker testing is necessary to facilitate individualized treatment of lung cancer patients. More than 80% of lung cancers are diagnosed based on very small tumor samples. Often there is not enough tissue for molecular analysis. We compared three minimal invasive sampling methods with respect to RNA quantity for molecular testing. Methods 106 small biopsies were prospectively collected by three different methods forceps biopsy, endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA), and CT-guided core biopsy. Samples were split into two halves. One part was formalin fixed and paraffin embedded for standard pathological evaluation. The other part was put in RNAlater for immediate RNA/DNA extraction. If the pathologist confirmed the diagnosis of non-small cell lung cancer(NSCLC), the following molecular markers were tested: EGFR mutation, ERCC1, RRM1 and BRCA1. Results Overall, RNA-extraction was possible in 101 out of 106 patients (95.3%). We found 49% adenocarcinomas, 38% squamouscarcinomas, and 14% non-otherwise-specified(NOS). The highest RNA yield came from endobronchial ultrasound guided needle aspiration, which was significantly higher than bronchoscopy (37.74±41.09 vs. 13.74±15.53 ng respectively, P = 0.005) and numerically higher than CT-core biopsy (37.74±41.09 vs. 28.72±44.27 ng respectively, P = 0.244). EGFR mutation testing was feasible in 100% of evaluable patients and its incidence was 40.8%, 7.9% and 14.3% in adenocarcinomas, squamouscarcinomas and NSCLC NOS subgroup respectively. There was no difference in the feasibility of molecular testing between the three sampling methods with feasibility rates for ERCC1, RRM1 and BRCA1 of 91%, 87% and 81% respectively. Conclusion All three methods can provide sufficient tumor material for multiple biomarkers testing from routinely obtained small biopsies in lung cancer patients. In our study EBUS guided needle aspiration provided the highest amount of

Renal Mass Biopsy to Guide Treatment Decisions for Small Incidental Renal Tumors: A Cost-effectiveness Analysis1

PubMed Central

Gervais, Debra A.; Hartman, Rebecca I.; Harisinghani, Mukesh G.; Feldman, Adam S.; Mueller, Peter R.; Gazelle, G. Scott

2010-01-01

Purpose: To evaluate the effectiveness, cost, and cost-effectiveness of using renal mass biopsy to guide treatment decisions for small incidentally detected renal tumors. Materials and Methods: A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for patients with small (≤4-cm) renal tumors. Two strategies were compared: renal mass biopsy to triage patients to surgery or imaging surveillance and empiric nephron-sparing surgery. The model incorporated biopsy performance, the probability of track seeding with malignant cells, the prevalence and growth of benign and malignant tumors, treatment effectiveness and costs, and patient outcomes. An incremental cost-effectiveness analysis was performed to identify strategy preference under a willingness-to-pay threshold of $75 000 per quality-adjusted life-year (QALY). Effects of changes in key parameters on strategy preference were evaluated in sensitivity analysis. Results: Under base-case assumptions, the biopsy strategy yielded a minimally greater quality-adjusted life expectancy (4 days) than did empiric surgery at a lower lifetime cost ($3466), dominating surgery from a cost-effectiveness perspective. Over the majority of parameter ranges tested in one-way sensitivity analysis, the biopsy strategy dominated surgery or was cost-effective relative to surgery based on a $75 000-per-QALY willingness-to-pay threshold. In two-way sensitivity analysis, surgery yielded greater life expectancy when the prevalence of malignancy and propensity for biopsy-negative cancers to metastasize were both higher than expected or when the sensitivity and specificity of biopsy were both lower than expected. Conclusion: The use of biopsy to guide treatment decisions for small incidentally detected renal tumors is cost-effective and can prevent unnecessary surgery in many cases. © RSNA, 2010 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10092013/-/DC1 PMID

21 CFR 876.5160 - Urological clamp for males.

Code of Federal Regulations, 2010 CFR

2010-04-01

... temporarily. It is an external clamp. (b) Classification. Class I (general controls). Except when intended for internal use or use on females, the device is exempt from the premarket notification procedures in subpart...

Safety evaluation of large external fixation clamps and frames in a magnetic resonance environment.

PubMed

Luechinger, Roger; Boesiger, Peter; Disegi, John A

2007-07-01

Large orthopedic external fixation clamps and related components were evaluated for force, torque, and heating response when subjected to the strong electromagnetic fields of magnetic-resonance (MR) imaging devices. Forces induced by a 3-Tesla (T) MR scanner were compiled for newly designed nonmagnetic clamps and older clamps that contained ferromagnetic components. Heating trials were performed in a 1.5 and in a 3 T MR scanner with two assembled external fixation frames. Forces of the newly designed clamps were more than a factor 2 lower as the gravitational force on the device whereas, magnetic forces on the older devices showed over 10 times the force induced by earth acceleration of gravity. No torque effects could be found for the newly designed clamps. Temperature measurements at the tips of Schanz screws in the 1.5 T MR scanner showed a rise of 0.7 degrees C for a pelvic frame and of 2.1 degrees C for a diamond knee bridge frame when normalized to a specific absorption rate (SAR) of 2 W/kg. The normalized temperature increases in the 3 T MR scanner were 0.9 degrees C for the pelvic frame and 1.1 degrees C for the knee bridge frame. Large external fixation frames assembled with the newly designed clamps (390 Series Clamps), carbon fiber reinforced rods, and implant quality 316L stainless steel Schanz screws met prevailing force and torque limits when tested in a 3-T field, and demonstrated temperature increase that met IEC-60601 guidelines for extremities. The influence of frame-induced eddy currents on the risk of peripheral nerve stimulation was not investigated. Copyright 2006 Wiley Periodicals, Inc.

Evaluation of Introduction of a Delayed Cord Clamping Protocol for Premature Neonates in a High-Volume Maternity Center.

PubMed

Liu, Lilly Y; Feinglass, Joe M; Khan, Janine Y; Gerber, Susan E; Grobman, William A; Yee, Lynn M

2017-05-01

To evaluate adherence to a delayed cord clamping protocol for preterm births in the first 2 years after its introduction, perform a quality improvement assessment, and determine neonatal outcomes associated with protocol implementation and adherence. This is a retrospective cohort study of women delivering singleton neonates at 23-32 weeks of gestation in the 2 years before (preprotocol) and 2 years after (postprotocol) introduction of a 30-second delayed cord clamping protocol at a large-volume academic center. This policy was communicated to obstetric and pediatric health care providers and nurses and reinforced with intermittent educational reviews. Barriers to receiving delayed cord clamping were assessed using χ tests and multivariable logistic regression. Neonatal outcomes then were compared between all neonates in the preprotocol period and all neonates in the postprotocol period and between all neonates in the preprotocol period and neonates receiving delayed cord clamping in the postprotocol period using multivariable linear and logistic regression analyses. Of the 427 eligible neonates, 187 were born postprotocol. Of these, 53.5% (n=100) neonates received delayed cord clamping according to the protocol. The rate of delayed cord clamping preprotocol was 0%. Protocol uptake and frequency of delayed cord clamping increased over the 2 years after its introduction. In the postprotocol period, cesarean delivery was the only factor independently associated with failing to receive delayed cord clamping (adjusted odds ratio [OR] 0.49, 95% confidence interval [CI] 0.25-0.96). In comparison with the preprotocol period, those who received delayed cord clamping in the postprotocol period had significantly higher birth hematocrit (β=2.46, P=.007) and fewer blood transfusions in the first week of life (adjusted OR 0.49, 95% CI 0.25-0.96). After introduction of an institutional delayed cord clamping protocol followed by continued health care provider education and

Predictive factors for positive diagnosis of malignant biliary strictures by transpapillary brush cytology and forceps biopsy.

PubMed

Naitoh, Itaru; Nakazawa, Takahiro; Kato, Akihisa; Hayashi, Kazuki; Miyabe, Katsuyuki; Shimizu, Shuya; Kondo, Hiromu; Nishi, Yuji; Yoshida, Michihiro; Umemura, Shuichiro; Hori, Yasuki; Kuno, Toshiya; Takahashi, Satoru; Ohara, Hirotaka; Joh, Takashi

2016-01-01

The diagnostic yields of endoscopic transpapillary brush cytology and forceps biopsies for malignant biliary strictures (MBS) remain unclear and predictive factors for diagnosis have not been established. We aimed to clarify the diagnostic yields of both methods and the predictive factors We reviewed 241 patients with biliary strictures who underwent transpapillary brush cytology (n = 202) or forceps biopsy (n= 208) between 2004 and 2014 at a single academic center. The sensitivity of forceps biopsy for MBS was significantly higher than that of brush cytology [60.6% (97/160) vs 36.1% (57/158), P < 0.01). The sensitivity of forceps biopsy was significantly higher in diagnosing bile duct cancer than pancreatic cancer [78.8% (52/66) vs 42.4% (28/66), P < 0.01). Multivariate analysis revealed that serum total bilirubin (TB) level (T-Bil) ≥ 4 mg/dL [odds ratio (OR) 2.506, 95% confidence interval (CI): 1.139-5.495, P = 0.022) was an independent predictor for positive diagnosis by brush cytology, while bile duct cancer (OR 4.926, 95% CI 2.183-11.111, P < 0.001), stricture length ≥ 30 mm (OR 2.941, 95% CI 1.119-7.752, P = 0.029) and TB ≥ 4 mg/dL (OR 2.252, 95% CI 1.052-4.831, P = 0.037) were significant indicators of a positive diagnosis by forceps biopsy. Endoscopic transpapillary forceps biopsy shows higher sensitivity than that of brush cytology for MBS. Bile duct cancer, stricture length ≥ 30 mm and TB ≥ 4 mg/dL are good indicators of forceps biopsy. © 2016 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Timing of umbilical cord-clamping and infant anaemia: the role of maternal anaemia.

PubMed

Blouin, Brittany; Penny, Mary E; Maheu-Giroux, Mathieu; Casapía, Martín; Aguilar, Eder; Silva, Hermánn; Creed-Kanashiro, Hilary M; Joseph, Serene A; Gagnon, Anita; Rahme, Elham; Gyorkos, Theresa W

2013-05-01

Evidence from randomized controlled trials has shown that delayed cord-clamping is beneficial to infant iron status. The role of maternal anaemia in this relationship, however, has not been established. To determine the effect of maternal anaemia at delivery on the association between timing of umbilical cord-clamping and infant anaemia at 4 and 8 months of age. A cohort of pregnant women admitted to the labour room of Hospital Iquitos (Iquitos, Peru) and their newborns were recruited into the study during two time periods (18 May to 3 June and 6-20 July 2009). Between the two recruitment periods, the hospital's policy changed from early to delayed umbilical cord-clamping. Maternal haemoglobin levels were measured before delivery, and the time between delivery and cord-clamping was recorded at delivery for the entire cohort. Mother-infant pairs were followed-up at 4 (n = 207) and 8 months (n = 184) post partum. Infant haemoglobin levels were measured at follow-up visits. Data were analysed using logistic regression models. The prevalence of maternal anaemia (Hb <11.0 g/dl) at delivery was 22%. Infant haemoglobin levels at 4 and 8 months of age were 10.4 g/dl and 10.3 g/dl, respectively. Infant haemoglobin levels did not differ significantly between infants born to anaemic mothers and those born to non-anaemic mothers at either 4 or 8 months of age. However, the association between the timing of cord-clamping and infant anaemia was modified by the mother's anaemia status. Significant benefits of delayed cord-clamping in preventing anaemia were found in infants born to anaemic mothers at both 4 months (aOR = 0.59, 95% CI 0.36-0.99) and 8 months (aOR = 0.38, 95% CI 0.19-0.76) of age. The study contributes additional evidence in support of delayed cord-clamping. This intervention is likely to have most public health impact in areas with a high prevalence of anaemia during pregnancy.

Safety and Feasibility of Pleural Cryobiopsy Compared to Forceps Biopsy During Semi-rigid Pleuroscopy.

PubMed

Pathak, Vikas; Shepherd, Ray W; Hussein, Ehab; Malhotra, Rajiv

2017-06-01

Pleural biopsy is often obtained in patients with undiagnosed exudative pleural effusion during pleuroscopy. Standard forceps have been traditionally used for the biopsy. Cryoprobes are being increasingly used for transbronchial lung biopsy as they obtain larger specimens and have less crush artifact. However, the safety and feasibility of cryoprobe biopsy compared to standard forceps for pleural biopsy has not been fully assessed. The objective of this study was to demonstrate the safety and feasibility of cryoprobe biopsy in the pleural space using semi-rigid pleuroscopy. Patients with idiopathic exudative pleural effusions underwent pleuroscopy. The procedure was done in the endoscopy suite with full barrier precautions and moderate sedation. Pleural biopsies were initially taken with a 2.0-mm saw-toothed forceps followed by a 2.4-mm cryoprobe (ERBECRYO, ERBE, US). The freeze time for each biopsy was 3 s. There were a total of ten patients, five males and five females. The mean age was 69 years (SD ± 11 years). The mean number of biopsies taken from the parietal pleura using forceps was 4.5 (SD ± 1.5) vs. 3.7 (SD ± 1.4) using cryoprobe. The mean cumulative tissue volume with forceps biopsy was 80 cu. mm; the mean cumulative tissue volume with cryobiopsy was 320 cu. mm, p = 0.007. The diagnostic yields were similar in both the groups. There was no increased incidence of bleeding, chest wall injury, or pain using cryoprobe in any of the patients. The use of cryoprobe for parietal pleural biopsy via semi-rigid pleuroscopy was feasible and safe in this small pilot study.

Ultrasound-Guided Breast Biopsy

MedlinePlus

... the type of biopsy being performed or the design of the biopsy machine, a biopsy of tissue ... cost information. The costs for specific medical imaging tests, treatments and procedures may vary by geographic region. ...

Abdominal wall fat pad biopsy

MedlinePlus

Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... most common method of taking an abdominal wall fat pad biopsy . The health care provider cleans the ...

Diagnosis of Hepatocellular Carcinoma Complicating Liver Cirrhosis: Utility of Repeat Ultrasound-Guided Biopsy after Unsuccessful First Sampling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caturelli, Eugenio; Biasini, Elisabetta; Bartolucci, Francesca

2002-08-15

Purpose: To evaluate the utility of a second ultrasound-guided fine-needle biopsy of liver nodules thought to be hepatocellular carcinoma when the original biopsy has failed to provide a reliable diagnosis. Methods: Thirty-seven cirrhotic patients underwent ultrasound-guided fine-needle biopsy of liver nodules that were subsequently diagnosed as hepatocellular carcinoma. Each biopsy involved a single puncture with a 20 G cutting needle, which yielded pathologic material used both for cytologic and histologic studies. In 23 cases (mean diameter of nodules 48 mm) the biopsy furnished exclusively necrotic material (non-diagnostic subgroup); in the other 14 cases (mean diameter 26 mm) the biopsy yieldedmore » no neoplastic elements (false-negative subgroup). All 37 nodules were subjected to repeat biopsies performed in the same manner. Results: The repeat biopsies provided a diagnosis of hepatocellular carcinoma in six of the 23 patients from the non-diagnostic subgroup and in seven of the 14 in the false-negative subgroup. Overall, repeat biopsy produced a diagnostic gain of 35.1%. Conclusion: The chance of success with repeat biopsy of hepatocellular carcinoma is limited and may depend to some extent on the characteristics of the lesions (i.e., areas of necrosis in large nodules, well-differentiated cellular populations in small ones)« less

Urinary urea nitrogen excretion during the hyperinsulinemic euglycemic clamp in type 1 diabetic patients and healthy subjects.

PubMed

Wohl, P; Krusinová, E; Klementová, M; Wohl, P; Kratochvílová, S; Pelikánová, T

2008-01-01

The hyperinsulinemic euglycemic clamp (HEC) combined with indirect calorimetry (IC) is used for estimation of insulin-stimulated substrate utilization. Calculations are based on urinary urea nitrogen excretion (UE), which is influenced by correct urine collection. The aims of our study were to improve the timing of urine collection during the clamp and to test the effect of insulin on UE in patients with type 1 diabetes (DM1; n=11) and healthy subjects (C; n=11). Urine samples were collected (a) over 24 h divided into 3-h periods and (b) before and during two-step clamp (1 and 10 mIU.kg(-1).min(-1); period 1 and period 2) combined with IC. The UE during the clamp was corrected for changes in urea pool size (UEc). There were no significant differences in 24-h UE between C and DM1 and no circadian variation in UE in either group. During the clamp, serum urea decreased significantly in both groups (p<0.01). Therefore, UEc was significantly lower as compared to UE not adjusted for changes in urea pool size both in C (p<0.001) and DM1 (p<0.001). While UE did not change during the clamp, UEc decreased significantly in both groups (p<0.01). UEc during the clamp was significantly higher in DM1 compared to C both in period 1 (p<0.05) and period 2 (p<0.01). The UE over 24 h and UEc during the clamp were statistically different in both C and DM1. We conclude that urine collection performed during the clamp with UE adjusted for changes in urea pool size is the most suitable technique for measuring substrate utilization during the clamp both in DM1 and C. Urine collections during the clamp cannot be replaced either by 24-h sampling (periods I-VII) or by a single 24-h urine collection. Attenuated insulin-induced decrease in UEc in DM1 implicates the impaired insulin effect on proteolysis.

The optimal protocol to reduce blood loss and blood transfusion after unilateral total knee replacement: Low-dose IA-TXA plus 30-min drain clamping versus drainage clamping for the first 3 h without IA-TXA.

PubMed

Park, Joo Hyun; Choi, Sung Wook; Shin, Eun Ho; Park, Myung Hoon; Kim, Myung Ku

2017-01-01

Although intraarticular tranexamic acid (IA-TXA) administration or drainage clamping are popular methods used to reduce blood loss after total knee replacement (TKR), the protocol remains controversial. We aimed (1) to establish new protocols through investigating whether two methods, that is, low-dose (500 mg) IA-TXA plus 30-min drain clamping and drainage clamping for the first 3 h without IA-TXA, can reduce blood loss and blood transfusion after unilateral TKR and (2) to make recommendations related to clinical application. This study, conducted from September 2014 to June 2016 related to enrolled 95 patients with primary osteoarthritis who were to have a unilateral cemented TKR, was nonrandomized and retrospective. In group A, the drain was released following tourniquet deflation. In group B, 500-mg TXA was injected into the knee joint via a drain tube after fascia closure and the drain was clamped for the first 30 min to prevent leakage. In group C, the drain was clamped for the first 3-h postoperation. Demographic characteristics and clinical data were collected, including the levels of hematocrit (Hct), the total blood loss (TBL), drained blood volume (BV), the amount of blood transfused, and any complications that developed. We found a significantly lower postoperative TBL, drained BV, decreasing Hct level, and less transfused BV in the IA-TXA injection group (group B) and the 3-h drainage clamping group (group C) compared to the conventional negative drainage group (group A; p < 0.001). There was no significant difference between groups B and C ( p = 0.99). The drainage clamping method can be safer than IA-TXA administration in patients with risk factor of venous thromboembolic complication. Furthermore, the IA-TXA administration can be more optimal than drainage clamping in patients with high bleeding tendency or lateral retinacular release during TKR, who would be concerned about postoperative wound complication.

LabPatch, an acquisition and analysis program for patch-clamp electrophysiology.

PubMed

Robinson, T; Thomsen, L; Huizinga, J D

2000-05-01

An acquisition and analysis program, "LabPatch," has been developed for use in patch-clamp research. LabPatch controls any patch-clamp amplifier, acquires and records data, runs voltage protocols, plots and analyzes data, and connects to spreadsheet and database programs. Controls within LabPatch are grouped by function on one screen, much like an oscilloscope front panel. The software is mouse driven, so that the user need only point and click. Finally, the ability to copy data to other programs running in Windows 95/98, and the ability to keep track of experiments using a database, make LabPatch extremely versatile. The system requirements include Windows 95/98, at least a 100-MHz processor and 16 MB RAM, a data acquisition card, digital-to-analog converter, and a patch-clamp amplifier. LabPatch is available free of charge at http://www.fhs.mcmaster.ca/huizinga/.

CLAMP - a toolkit for efficiently building customized clinical natural language processing pipelines.

PubMed

Soysal, Ergin; Wang, Jingqi; Jiang, Min; Wu, Yonghui; Pakhomov, Serguei; Liu, Hongfang; Xu, Hua

2017-11-24

Existing general clinical natural language processing (NLP) systems such as MetaMap and Clinical Text Analysis and Knowledge Extraction System have been successfully applied to information extraction from clinical text. However, end users often have to customize existing systems for their individual tasks, which can require substantial NLP skills. Here we present CLAMP (Clinical Language Annotation, Modeling, and Processing), a newly developed clinical NLP toolkit that provides not only state-of-the-art NLP components, but also a user-friendly graphic user interface that can help users quickly build customized NLP pipelines for their individual applications. Our evaluation shows that the CLAMP default pipeline achieved good performance on named entity recognition and concept encoding. We also demonstrate the efficiency of the CLAMP graphic user interface in building customized, high-performance NLP pipelines with 2 use cases, extracting smoking status and lab test values. CLAMP is publicly available for research use, and we believe it is a unique asset for the clinical NLP community. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Endobronchial Ultrasound-guided Transbronchial Needle Aspiration Increases the Yield of Transbronchial Lung Biopsy for the Evaluation of Peribronchial Lesions

PubMed Central

Chen, Cheng; Mu, Chuan-Yong; Su, Mei-Qin; Mao, Jing-Yu; Zhu, Ye-Han; Huang, Jian-An

2017-01-01

Background: Due to absence of visible endobronchial target, the diagnostic yield of flexible bronchoscopy for peribronchial lesions has been unsatisfactory. Convex probe endobronchial ultrasound (CP-EBUS) has allowed for performing real-time transbronchial needle aspiration (TBNA) of enlarged hilar and mediastinal lymph nodes and therefore could also be used as a means of diagnosing proximal peribronchial lesions. Methods: We retrospectively analyzed the results related to 72 patients who underwent CP-EBUS for peribronchial lesions without endobronchial involvement and adjacent to three-grade bronchi based on chest computed tomography (CT) scan. We recorded the images during EBUS as well as the diagnostic results of TBNA and conventional-transbronchial lung biopsy/brush (C-TBLB/b), and final diagnoses were based on pathologic analysis and follow-up. Results: In all cases, the mass was able to be identified using EBUS in 97.2% patients (70/72) who were performed with EBUS-TBNA + C-TBLB/b. Sixty-six patients had a final diagnosis, 80.0% patients (56/70) had malignancies, and 14.3% patients (10/70) had benign disease. In malignancies, the diagnostic yield of C-TBLB/b was 57.1% (32/56) and in EBUS-TBNA was 85.7% (48/56), whereas pathologic diagnosis reached 94.6% when EBUS-TBNA was combined with C-TBLB/b. C-TBLB/b + EBUS-TBNA also exhibited stronger potency of histolytic diagnosis for malignancies than either EBUS-TBNA or C-TBLB/b alone. Furthermore, there are data supporting the value of EBUS-TBNA for the diagnosis of benign lung disease. Conclusion: The combined endoscopic approach with EBUS-TBNA and C-TBLB/b is an accurate and effective method for the evaluation of peribronchial lesions, with better results than using each technique alone. PMID:28051017

Improved specimen adequacy using jumbo biopsy forceps in patients with Barrett's esophagus

PubMed Central

Martinek, Jan; Maluskova, Jana; Stefanova, Magdalena; Tuckova, Inna; Suchanek, Stepan; Vackova, Zuzana; Krajciova, Jana; Kollar, Marek; Zavoral, Miroslav; Spicak, Julius

2015-01-01

AIM: To assess the sampling quality of four different forceps (three large capacity and one jumbo) in patients with Barrett’s esophagus. METHODS: This was a prospective, single-blind study. A total of 37 patients with Barrett’s esophagus were enrolled. Targeted or random biopsies with all four forceps were obtained from each patient using a diagnostic endoscope during a single endoscopy. The following forceps were tested: A: FB-220K disposable large capacity; B: BI01-D3-23 reusable large capacity; C: GBF-02-23-180 disposable large capacity; and jumbo: disposable Radial Jaw 4 jumbo. The primary outcome measurement was specimen adequacy, defined as a well-oriented biopsy sample 2 mm or greater with the presence of muscularis mucosa. RESULTS: A total of 436 biopsy samples were analyzed. We found a significantly higher proportion of adequate biopsy samples with jumbo forceps (71%) (P < 0.001 vs forceps A: 26%, forceps B: 17%, and forceps C: 18%). Biopsies with jumbo forceps had the largest diameter (median 2.4 mm) (P < 0.001 vs forceps A: 2 mm, forceps B: 1.6 mm, and forceps C: 2mm). There was a trend for higher diagnostic yield per biopsy with jumbo forceps (forceps A: 0.20, forceps B: 0.22, forceps C: 0.27, and jumbo: 0.28). No complications related to specimen sampling were observed with any of the four tested forceps. CONCLUSION: Jumbo biopsy forceps, when used with a diagnostic endoscope, provide more adequate specimens as compared to large-capacity forceps in patients with Barrett’s esophagus. PMID:25954107

Improved specimen adequacy using jumbo biopsy forceps in patients with Barrett's esophagus.

PubMed

Martinek, Jan; Maluskova, Jana; Stefanova, Magdalena; Tuckova, Inna; Suchanek, Stepan; Vackova, Zuzana; Krajciova, Jana; Kollar, Marek; Zavoral, Miroslav; Spicak, Julius

2015-05-07

To assess the sampling quality of four different forceps (three large capacity and one jumbo) in patients with Barrett's esophagus. This was a prospective, single-blind study. A total of 37 patients with Barrett's esophagus were enrolled. Targeted or random biopsies with all four forceps were obtained from each patient using a diagnostic endoscope during a single endoscopy. The following forceps were tested: A: FB-220K disposable large capacity; B: BI01-D3-23 reusable large capacity; C: GBF-02-23-180 disposable large capacity; and jumbo: disposable Radial Jaw 4 jumbo. The primary outcome measurement was specimen adequacy, defined as a well-oriented biopsy sample 2 mm or greater with the presence of muscularis mucosa. A total of 436 biopsy samples were analyzed. We found a significantly higher proportion of adequate biopsy samples with jumbo forceps (71%) (P < 0.001 vs forceps A: 26%, forceps B: 17%, and forceps C: 18%). Biopsies with jumbo forceps had the largest diameter (median 2.4 mm) (P < 0.001 vs forceps A: 2 mm, forceps B: 1.6 mm, and forceps C: 2mm). There was a trend for higher diagnostic yield per biopsy with jumbo forceps (forceps A: 0.20, forceps B: 0.22, forceps C: 0.27, and jumbo: 0.28). No complications related to specimen sampling were observed with any of the four tested forceps. Jumbo biopsy forceps, when used with a diagnostic endoscope, provide more adequate specimens as compared to large-capacity forceps in patients with Barrett's esophagus.

Effect of complete hilar versus only renal artery clamping on renal histomorphology following ischemia/reperfusion injury in an experimental model.

PubMed

Umul, M; Cal, A C; Turna, B; Oktem, G; Aydın, H H

2016-01-01

To evaluate the effect of temporary complete hilar versus only renal artery clamping with different duration of warm ischemia on renal functions, and possibly identify a "safe" clamping type and duration of renal ischemia. Fifty male rabbits have been incorporated to study. Rabbits were subjected to ischemia/reperfusion injury by temporary vascular clamping. Reagents were randomized to 3 experimental groups (only renal artery clamping, complete hilar clamping, sham surgery) and sub-groups were determined according to different clamping times (30 and 60 minutes). Median laparotomy and left renal hilus dissection were performed to sham group. Only artery or complete hilar clamping was performed for 30 or 60 minutes by microvascular bulldog clamps to other reagents. Rabbits were sacrificed 10 days after primary surgery and left nephrectomy performed. Nephrectomy materials were evaluated for the level of nitric-oxide synthase (NOS) immunoreactivity, malondialdehyde (MDA) level and superoxide dismutase (SOD) activity and an electron microscopic examination was performed. NOS immunoreactivity was correlated with the temporary clamping time. We also observed that complete hilar vascular clamping entails an increase on NOS immunoreactivity. MDA levels were similar for all experimental surgery groups (p = 0.42). The SOD activity was decreased among all subgroups compared with sham surgery. But the significant decrease occurred in 30 minutes only artery and 30 minutes complete hilar clamping groups in proportion to sham surgery (p = 0.026 and p = 0.019, respectively). This current study suggested that only renal artery clamping under 30 minutes is more appropriate during renal surgical procedures requiring temporary vascular clamping.

Target motion tracking in MRI-guided transrectal robotic prostate biopsy.

PubMed

Tadayyon, Hadi; Lasso, Andras; Kaushal, Aradhana; Guion, Peter; Fichtinger, Gabor

2011-11-01

MRI-guided prostate needle biopsy requires compensation for organ motion between target planning and needle placement. Two questions are studied and answered in this paper: 1) is rigid registration sufficient in tracking the targets with an error smaller than the clinically significant size of prostate cancer and 2) what is the effect of the number of intraoperative slices on registration accuracy and speed? we propose multislice-to-volume registration algorithms for tracking the biopsy targets within the prostate. Three orthogonal plus additional transverse intraoperative slices are acquired in the approximate center of the prostate and registered with a high-resolution target planning volume. Both rigid and deformable scenarios were implemented. Both simulated and clinical MRI-guided robotic prostate biopsy data were used to assess tracking accuracy. average registration errors in clinical patient data were 2.6 mm for the rigid algorithm and 2.1 mm for the deformable algorithm. rigid tracking appears to be promising. Three tracking slices yield significantly high registration speed with an affordable error.

Synthetic polymers as substrates for a DNA-sliding clamp protein.

PubMed

van Dongen, S F M; Clerx, J; van den Boomen, O I; Pervaiz, M; Trakselis, M A; Ritschel, T; Schoonen, L; Schoenmakers, D C; Nolte, R J M

2018-04-26

The clamp protein (gp45) of the DNA polymerase III of the bacteriophage T4 is known to bind to DNA and stay attached to it in order to facilitate the process of DNA copying by the polymerase. As part of a project aimed at developing new biomimetic data-encoding systems we have investigated the binding of gp45 to synthetic polymers, that is, rigid, helical polyisocyanopeptides. Molecular modelling studies suggest that the clamp protein may interact with the latter polymers. Experiments aimed at verifying these interactions are presented and discussed. © 2018 The Authors Biopolymers Published by Wiley Periodicals, Inc.

Anxiety prior to breast biopsy: Relationships with length of time from breast biopsy recommendation to biopsy procedure and psychosocial factors.

PubMed

Hayes Balmadrid, Melissa A; Shelby, Rebecca A; Wren, Anava A; Miller, Lauren S; Yoon, Sora C; Baker, Jay A; Wildermann, Liz A; Soo, Mary Scott

2017-04-01

This study investigated how time from breast biopsy recommendation to biopsy procedure affected pre-biopsy anxiety ( N = 140 women), and whether the relationship between wait time and anxiety was affected by psychosocial factors (chronic life stress, traumatic events, social support). Analyses showed a significant interaction between wait time and chronic life stress. Increased time from biopsy recommendation was associated with greater anxiety in women with low levels of life stress. Women with high levels of life stress experienced increased anxiety regardless of wait time. These results suggest that women may benefit from shorter wait times and receiving strategies for managing anxiety.

A novel way to go whole-cell in patch-clamp experiments.

PubMed

Inayat, Samsoon; Zhao, Yan; Cantrell, Donal R; Dikin, Dmitryi; Pinto, Lawrence H; Troy, John B

2010-11-01

With a conventional patch-clamp electrode, an Ag/AgCl wire sits stationary inside the pipette. To move from the gigaseal cell-attached configuration to whole-cell recording, suction is applied inside the pipette. We have designed and developed a novel Pushpen patch-clamp electrode, in which a W wire insulated and wound with Ag/AgCl wire can move linearly inside the pipette. The W wire has a conical tip, which can protrude from the pipette tip like a push pen, a procedure we call the Pushpen Operation. We use the Pushpen operation to impale the cell membrane in cell-attached configuration to go whole-cell without disruption of the gigaseal. We successfully recorded whole-cell currents from chinese hamster ovarian cells expressing influenza A virus protein A/M2, after obtaining whole-cell configuration with the Pushpen operation. This novel method of achieving whole-cell configuration may have a higher success rate than is the case with the conventional patch clamp technique.

Randomized clinical trial of stapler versus clamp-crushing transection in elective liver resection.

PubMed

Rahbari, N N; Elbers, H; Koch, M; Vogler, P; Striebel, F; Bruckner, T; Mehrabi, A; Schemmer, P; Büchler, M W; Weitz, J

2014-02-01

Various devices have been developed to facilitate liver transection and reduce blood loss in liver resections. None of these has proven superiority compared with the classical clamp-crushing technique. This randomized clinical trial compared the effectiveness and safety of stapler transection with that of clamp-crushing during open liver resection. Patients admitted for elective open liver resection between January 2010 and October 2011 were assigned randomly to stapler transection or the clamp-crushing technique. The primary endpoint was the total amount of intraoperative blood loss. Secondary endpoints included transection time, duration of operation, complication rates and resection margins. A total of 130 patients were enrolled, 65 to clamp-crushing and 65 to stapler transection. There was no difference between groups in total intraoperative blood loss: median (i.q.r.) 1050 (525-1650) versus 925 (450-1425) ml respectively (P = 0·279). The difference in total intraoperative blood loss normalized to the transection surface area was not statistically significant (P = 0·092). Blood loss during parenchymal transection was significantly lower in the stapler transection group (P = 0·002), as were the parenchymal transection time (mean(s.d.) 30(21) versus 9(7) min for clamp-crushing and stapler transection groups respectively; P < 0·001) and total duration of operation (mean(s.d.) 221(86) versus 190(85) min; P = 0·047). There were no significant differences in postoperative morbidity (P = 0·863) or mortality (P = 0·684) between groups. Stapler transection is a safe technique but does not reduce intraoperative blood loss in elective liver resection compared with the clamp-crushing technique. NCT01049607 (http://www.clinicaltrials.gov). © 2014 BJS Society Ltd. Published by John Wiley & Sons Ltd.

Clinical application of Lin's biopsy grasper for intrauterine targeted biopsy and polypectomy during office hysteroscopy.

PubMed

Cheng, Hsin-Yi; Lin, Bao-Liang; Tseng, Jen-Yu; Ueno, Kazunori; Nakada, Sakura

2018-06-01

Hysteroscopy has widely been used for diagnosis of the uterine cavity; however, target biopsy has often been difficult in part to the inherent limitations of ancillary instruments. Lin's biopsy grasper was specifically designed to work in conjunction with a flexible hysteroscope to obtain intrauterine biopsy under transabdominal sonography. Herein, we share our clinical experience in the management of endometrial abnormalities with the use of Lin's biopsy grasper during office-based hysteroscopy. From February 2006 to November 2016, the use of Lin's biopsy grasper for tissue biopsy was attempted on 126 cases. We retrospectively recorded and analyzed the patients' preoperative characteristics and biopsy outcomes to demonstrate the feasibility and efficacy of Lin's biopsy grasper. Out of the one hundred and twenty-six enrolled patients, satisfactory targeted biopsies were achieved; including high diagnostic rate (92.1%, with 116 cases confirmed histologically) and adequate tissue retrieval (77.8%, with 98 cases obtaining optimal specimen volume). All patients tolerated the procedure without analgesics or anesthesia. Diagnostic flexible hysteroscopy combined with the use of Lin's biopsy grasper has proven to be an effective tool for intrauterine evaluation and obtaining tissue sample. Copyright © 2018. Published by Elsevier B.V.

Substrate clamping effects on irreversible domain wall dynamics in lead zirconate titanate thin films.

PubMed

Griggio, F; Jesse, S; Kumar, A; Ovchinnikov, O; Kim, H; Jackson, T N; Damjanovic, D; Kalinin, S V; Trolier-McKinstry, S

2012-04-13

The role of long-range strain interactions on domain wall dynamics is explored through macroscopic and local measurements of nonlinear behavior in mechanically clamped and released polycrystalline lead zirconate-titanate (PZT) films. Released films show a dramatic change in the global dielectric nonlinearity and its frequency dependence as a function of mechanical clamping. Furthermore, we observe a transition from strong clustering of the nonlinear response for the clamped case to almost uniform nonlinearity for the released film. This behavior is ascribed to increased mobility of domain walls. These results suggest the dominant role of collective strain interactions mediated by the local and global mechanical boundary conditions on the domain wall dynamics. The work presented in this Letter demonstrates that measurements on clamped films may considerably underestimate the piezoelectric coefficients and coupling constants of released structures used in microelectromechanical systems, energy harvesting systems, and microrobots.

Constant-frequency, clamped-mode resonant converters

NASA Technical Reports Server (NTRS)

Tsai, Fu-Sheng; Materu, Peter; Lee, Fred C.

1987-01-01

Two novel clamped-mode resonant converters are proposed which operate at a constant frequency while retaining many desired features of conventional series- and parallel-resonant converters. State-plane analysis techniques are used to identify all possible operating modes and define their mode boundaries. Control-to-output characteristics are derived that specify the regions for natural and forced commutation. The predicted operating modes are verified using a prototype circuit.

Sodium efflux from voltage clamped squid giant axons.

PubMed Central

Landowne, D

1977-01-01

1. The efflux of radioactive sodium was measured from squid axons during simultaneous voltage clamp experiments such that it was possible to determine the efflux of sodium associated with a measured voltage clamp current. 2. The extra efflux of sodium associated with voltage clamp pulses increased linearly with the magnitude of the depolarization above 40 mV. A 100 mV pulse of sufficient duration to produce all of the sodium current increased the rate constant of efflux by about 10(-6). 3. Application of 100 nM tetrodotoxin eliminated the sodium current and the extra efflux of radioactive sodium. 4. Cooling the axon increased the extra efflux/voltage clamp pulse slightly with a Q10 of 1/1-1. On the same axons cooling increased the integral of the sodium current with a Q10 of 1/1-4. 5. Replacing external sodium with Tris, dextrose or Mg-mannitol reduced the extra efflux of sodium by about 50%. The inward sodium current was replaced with an outward current as expected. 6. Replacing external sodium with lithium also reduced the extra efflux by about 50% but the currents seen in lithium were slightly larger than those in sodium. 7. The effect of replacing external sodium was not voltage dependent. Cooling reduced the effect so that there was less reduction of efflux on switching to Tris ASW in the cold than in the warm. 8. The extra efflux of sodium into sodium-free ASW is approximately the same as the integral of the sodium current. Adding external sodium produces a deviation from the independence principle such that there is more exchange of sodium than predicted. Such a deviation from prediction was noted by Hodgkin & Huxley (1952c). 9. Using the equations of Hodgkin & Huxley (1952c) modified to include the deviation from independence reported in this paper and its temperature dependence, one can predict the temperature dependence of the sodium efflux associated with action potentials and obtain much better agreement than is possibly without these phenomena. 10

Intraoperative visualisation of functional structures facilitates safe frameless stereotactic biopsy in the motor eloquent regions of the brain.

PubMed

Zhang, Jia-Shu; Qu, Ling; Wang, Qun; Jin, Wei; Hou, Yuan-Zheng; Sun, Guo-Chen; Li, Fang-Ye; Yu, Xin-Guang; Xu, Ban-Nan; Chen, Xiao-Lei

2017-12-20

For stereotactic brain biopsy involving motor eloquent regions, the surgical objective is to enhance diagnostic yield and preserve neurological function. To achieve this aim, we implemented functional neuro-navigation and intraoperative magnetic resonance imaging (iMRI) into the biopsy procedure. The impact of this integrated technique on the surgical outcome and postoperative neurological function was investigated and evaluated. Thirty nine patients with lesions involving motor eloquent structures underwent frameless stereotactic biopsy assisted by functional neuro-navigation and iMRI. Intraoperative visualisation was realised by integrating anatomical and functional information into a navigation framework to improve biopsy trajectories and preserve eloquent structures. iMRI was conducted to guarantee the biopsy accuracy and detect intraoperative complications. The perioperative change of motor function and biopsy error before and after iMRI were recorded, and the role of functional information in trajectory selection and the relationship between the distance from sampling site to nearby eloquent structures and the neurological deterioration were further analyzed. Functional neuro-navigation helped modify the original trajectories and sampling sites in 35.90% (16/39) of cases to avoid the damage of eloquent structures. Even though all the lesions were high-risk of causing neurological deficits, no significant difference was found between preoperative and postoperative muscle strength. After data analysis, 3mm was supposed to be the safe distance for avoiding transient neurological deterioration. During surgery, the use of iMRI significantly reduced the biopsy errors (p = 0.042) and potentially increased the diagnostic yield from 84.62% (33/39) to 94.87% (37/39). Moreover, iMRI detected intraoperative haemorrhage in 5.13% (2/39) of patients, all of them benefited from the intraoperative strategies based on iMRI findings. Intraoperative visualisation of

Is there a role for anterior zone sampling as part of saturation trans-rectal ultrasound guided prostate biopsy?

PubMed

Cole, Eric; Margel, David; Greenspan, Michael; Shayegan, Bobby; Matsumoto, Edward; Fischer, Marc A; Patlas, Michael; Daya, Dean; Pinthus, Jehonathan H

2014-05-03

The prostatic anterior zone (AZ) is not targeted routinely by TRUS guided prostate biopsy (TRUS-Pbx). MRI is an accurate diagnostic tool for AZ tumors, but is often unavailable due to cost or system restrictions. We examined the diagnostic yield of office based AZ TRUS-Pbx. 127 men at risk for AZ tumors were studied: Patients with elevated PSA and previous extended negative TRUS-Pbx (group 1, n = 78) and actively surveyed low risk prostate cancer patients (group 2, n = 49). None of the participants had a previous AZ biopsy. Biopsy template included suspicious ultrasonic areas, 16 peripheral zone (PZ), 4 transitional zone (TZ) and 6 AZ cores. All biopsies were performed by a single urologist under local peri-prostatic anaesthetic, using the B-K Medical US System, an end-firing probe 4-12 MHZ and 18 ga/25 cm needle. All samples were reviewed by a single specialized uro-pathologist. Multivariate analysis was used to detect predictors for AZ tumors accounting for age, PSA, PSA density, prostate volume, BMI, and number of previous biopsies. Median PSA was 10.4 (group 1) and 7.3 (group 2). Age (63.9, 64.5), number of previous biopsies (1.5) and cores (17.8, 21.3) and prostate volume (56.4 cc, 51 cc) were similar for both groups. The overall diagnostic yield was 34.6% (group 1) and 85.7% (group 2). AZ cancers were detected in 21.8% (group 1) and 34.7% (group 2) but were rarely the only zone involved (1.3% and 4.1% respectively). Gleason ≥ 7 AZ cancers were often accompanied by equal grade PZ tumors. In multivariate analysis only prostate volume predicted for AZ tumors. Patients detected with AZ tumors had significantly smaller prostates (36.9 cc vs. 61.1 cc p < 0.001). Suspicious AZ ultrasonic findings were uncommon (6.3%). TRUS-Pbx AZ sampling rarely improves the diagnostic yield of extended PZ sampling in patients with elevated PSA and previous negative biopsies. In low risk prostate cancer patients who are followed by active surveillance, AZ sampling changes risk

Artery cross-clamping during laparoscopic vascular surgeries; a computational tactile sensing approach.

PubMed

Pahlavan, Pedram; Najarian, Siamak; Afshari, Elnaz; Moini, Majid

2013-01-01

Artificial palpation is one of the most valuable achievements of artificial tactile sensing approach that can be used in various fields of medicine and more specifically in surgery. These techniques cause different surgical maneuvers to be done more precisely and noninvasively. In this study, considering the present problems and limitations of cross-clamping an artery during laparoscopic vascular surgeries, a new tactile sensory system will be introduced.Having imitated surgeon's palpation during open vascular surgeries and modeled it conceptually, the optimal amount of the total angular displacement of each robot joint in order to cross-clamping an artery without damaging to the artery surrounding tissues will be calculated. The elastic governing equation of contact occurred between the tactile sensor placed on the first link of the robot and the surrounding tissues around the artery were developed. A finite element model is coupled with genetic algorithm optimization method so that the normal stress and displacements in contact surface of the robot and artery's surrounding tissues would be minimized. Thus, reliability and accuracy of artificial tactile sensing method in artery cross-clamping will be demonstrated. Finally, the functional principles of the new tactile system capable of cross-clamping an artery during laparoscopic surgeries will be presented.

Concordance of Gleason grading with three-dimensional ultrasound systematic biopsy and biopsy core pre-embedding.

PubMed

van der Aa, Anouk A M A; Mannaerts, Christophe K; van der Linden, Hans; Gayet, Maudy; Schrier, Bart Ph; Mischi, Massimo; Beerlage, Harrie P; Wijkstra, Hessel

2018-02-01

To determine the value of a three-dimensional (3D) greyscale transrectal ultrasound (TRUS)-guided prostate biopsy system and biopsy core pre-embedding method on concordance between Gleason scores of needle biopsies and radical prostatectomy (RP) specimens. Retrospective analysis of prostate biopsies and subsequent RP for PCa in the Jeroen Bosch Hospital, the Netherlands, from 2007 to 2016. Two cohorts were analysed: conventional 2D TRUS-guided biopsies and RP (2007-2013, n = 266) versus 3D TRUS-guided biopsies with pre-embedding (2013-2016, n = 129). The impact of 3D TRUS-guidance with pre-embedding on Gleason score (GS) concordance between biopsy and RP was evaluated using the κ-coefficient. Predictors of biopsy GS 6 upgrading were assessed using logistic regression models. Gleason concordance was comparable between the two cohorts with a κ = 0.44 for the 3D cohort, compared to κ = 0.42 for the 2D cohort. 3D TRUS-guidance with pre-embedding, did not significantly affect the risk of biopsy GS 6 upgrading in univariate and multivariate analysis. 3D TRUS-guidance with biopsy core pre-embedding did not improve Gleason concordance. Improved detection techniques are needed for recognition of low-grade disease upgrading.

Ultrasound-guided chest biopsies.

PubMed

Middleton, William D; Teefey, Sharlene A; Dahiya, Nirvikar

2006-12-01

Pulmonary nodules that are surrounded by aerated lung cannot be visualized with sonography. Therefore, percutaneous biopsy must be guided with computed tomography or fluoroscopy. Although this restriction only applies to central lung nodules, it has permeated referral patterns for other thoracic lesions and has retarded the growth of ultrasound-guided interventions. Nevertheless, sonography is an extremely flexible modality that can expeditiously guide many biopsy procedures in the thorax. Peripheral pulmonary nodules can be successfully biopsied with success rates exceeding 90% and complications rates of less than 5%. Orienting the probe parallel to the intercostal space facilitates biopsies of peripheral pulmonary nodules. Anterior mediastinal masses that extend to the parasternal region are often easily approachable provided the internal mammary vessels, costal cartilage, and deep great vessels are identified and avoided. Superior mediastinal masses can be sampled from a suprasternal or supraclavicular approach. Phased array probes or tightly curved arrays may provide improved access for biopsies in this location. Posterior mediastinal masses are more difficult to biopsy with ultrasound guidance because of the overlying paraspinal muscles. However, when posterior mediastinal masses extend into the posterior medial pleural region, they can be biopsied with ultrasound guidance. Because many lung cancers metastasize to the supraclavicular nodes, it is important to evaluate the supraclavicular region when determining the best approach to obtain a tissue diagnosis. When abnormal supraclavicular nodes are present, they often are the easiest and safest lesions to biopsy.

Technical note: The development of a methodology for ruminal and colon tissue biopsying of young Holstein dairy calves.

PubMed

van Niekerk, J K; Middeldorp, M; Steele, M A

2018-05-09

The objectives of this study were to develop a methodology for biopsying the rumen and colon of young dairy calves and to collect suitable quality tissue samples for microscopic and gene expression analysis. Six Holstein dairy bull calves (45.0 ± 1.5 kg birth weight) were ruminally cannulated during the second week of life and weaned at the end of wk 6. Ruminal and colon tissue samples were collected at the end of wk 5, 6, 7, 8, and 12. Calves were not sedated but were restrained in a chute for sampling. The endoscope (100 cm length, 9.8 mm diameter) was introduced through the rumen cannula to harvest ruminal tissue. Endoscopic biopsies of the rumen with endoscopic biopsy forceps were unsuccessful 85% of the time because they were unable to shear the ruminal tissue. Thereafter, an Allis clamp was used to retrieve the blind sac through the rumen cannula to perform direct tissue biopsying with surgical scissors. To biopsy the colon, the lubricated distal tip of an endoscope was slowly inserted into the calf's anus. A total of 6 colon tissue samples (12.6 ± 0.74 mg) were collected per calf per time point from the distal colon 30 to 40 cm from the calf's anus using endoscopic biopsy forceps, which were inserted through the instrument channel. A new forcep was used between sites and calves. Between calves, the outside of the endoscope was washed with 4% chlorohexidine and rinsed with water and the instrument channel was washed with distilled water and 70% ethanol. Colon and ruminal samples were processed for histological measurements, and RNA was isolated and sequenced. High-quality RNA (RNA integrity number 8.8 ± 0.08) was collected from samples, and light and electron microscopy was performed on samples. In conclusion, endoscopic biopsying can be used for tissue harvest in the colon of young calves. However, it was found that collecting ruminal tissue by retracting the rumen from the cannula and taking samples with surgical scissors was more successful than an

Accessible or Inaccessible? Diagnostic Efficacy of CT-Guided Core Biopsies of Head and Neck Masses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cunningham, Jane D., E-mail: janecunningham0708@gmail.com; McCusker, Mark W.; Power, Sarah

PurposeTissue sampling of lesions in the head and neck is challenging due to complex regional anatomy and sometimes necessitates open surgical biopsy. However, many patients are poor surgical candidates due to comorbidity. Thus, we evaluated the use of CT guidance for establishing histopathological diagnosis of head and neck masses.MethodsAll consecutive patients (n = 22) who underwent CT-guided core biopsy of head or neck masses between April 2009 and August 2012 were retrospectively reviewed using the departmental CT interventional procedures database. The indication for each biopsy performed was to establish or exclude a diagnosis of neoplasia in patients with suspicious head or neckmore » lesions found on clinical examination or imaging studies. Patients received conscious sedation and 18 G, semiautomated core needle biopsies were performed by experienced neuroradiologists using 16-slice multidetector row CT imaging guidance (Somatom Definition Siemens Medical Solutions, Germany). Histopathology results of each biopsy were analysed.ResultsSixteen of 22 biopsies that were performed (73 %) yielded a pathological diagnosis. Anatomic locations biopsied included: masticator (n = 7), parapharyngeal (n = 3), parotid (n = 3), carotid (n = 3), perivertebral (n = 3), pharyngeal (n = 2), and retropharyngeal (n = 1) spaces. Six biopsies (27 %) were nondiagnostic due to inadequate tissue sampling, particularly small biopsy sample size and failure to biopsy the true sampling site due to extensive necrosis. No major complications were encountered.ConclusionsThe use of CT guidance to perform core biopsies of head and neck masses is an effective means of establishing histopathological diagnosis and reduces the need for diagnostic open surgical biopsy and general anaesthesia.« less

Efficacy of tranexamic acid plus drain-clamping to reduce blood loss in total knee arthroplasty: A meta-analysis.

PubMed

Zhang, Yan; Zhang, Jun-Wei; Wang, Bao-Hua

2017-06-01

Perioperative blood loss is still an unsolved problem in total knee arthroplasty (TKA). The efficacy of the preoperative use of tranexamic acid (TXA) plus drain-clamping to reduce blood loss in TKA has been debated. This meta-analysis aimed to illustrate the efficacy of TXA plus drain-clamping to reduce blood loss in patients who underwent a TKA. In February 2017, a systematic computer-based search was conducted in PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews, and Google Scholar. Data from patients prepared for TKA in studies that compared TXA plus drain-clamping versus TXA alone, drain-clamping alone, or controls were retrieved. The primary endpoint was the need for transfusion. The secondary outcomes were total blood loss, blood loss in drainage, the decrease in hemoglobin, and the occurrence of deep venous thrombosis. After testing for publication bias and heterogeneity between studies, data were aggregated for random-effects models when necessary. Ultimately, 5 clinical studies with 618 patients (TXA plus drain-clamping group = 249, control group = 130, TXA-alone group = 60, and drain-clamping group = 179) were included. TXA plus drain-clamping could decrease the need for transfusion, total blood loss, blood loss in drainage, and the decrease in hemoglobin than could the control group, the TXA-alone group, and the drain-clamping group (P < .05). There was no significant difference between the occurrence of deep venous thrombosis between the included groups (P > .05). TXA plus drain-clamping can achieve the maximum effects of hemostasis in patients prepared for primary TKA. Because the number and the quality of the included studies were limited, more high-quality randomized controlled trials are needed to identify the optimal dose of TXA and the clamping hours in patients prepared for TKA.

Robotic Automation of In Vivo Two-Photon Targeted Whole-Cell Patch-Clamp Electrophysiology.

PubMed

Annecchino, Luca A; Morris, Alexander R; Copeland, Caroline S; Agabi, Oshiorenoya E; Chadderton, Paul; Schultz, Simon R

2017-08-30

Whole-cell patch-clamp electrophysiological recording is a powerful technique for studying cellular function. While in vivo patch-clamp recording has recently benefited from automation, it is normally performed "blind," meaning that throughput for sampling some genetically or morphologically defined cell types is unacceptably low. One solution to this problem is to use two-photon microscopy to target fluorescently labeled neurons. Combining this with robotic automation is difficult, however, as micropipette penetration induces tissue deformation, moving target cells from their initial location. Here we describe a platform for automated two-photon targeted patch-clamp recording, which solves this problem by making use of a closed loop visual servo algorithm. Our system keeps the target cell in focus while iteratively adjusting the pipette approach trajectory to compensate for tissue motion. We demonstrate platform validation with patch-clamp recordings from a variety of cells in the mouse neocortex and cerebellum. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Minimalist video-assisted thoracic surgery biopsy of mediastinal tumors.

PubMed

Tacconi, Federico; Rogliani, Paola; Cristino, Benedetto; Gilardi, Francesco; Palombi, Leonardo; Pompeo, Eugenio

2016-12-01

Mediastinal tumors often require surgical biopsy to achieve a precise and rapid diagnosis. However, subjects with mediastinal tumors may be unfit for general anesthesia, particularly when compression of major vessels or airways does occur. We tested the applicability in this setting of a minimalist (M) uniportal, video-assisted thoracic surgery (VATS) strategy carried out under locoregional anesthesia in awake patients (MVATS). We analyzed in a comparative fashion including propensity score matching, data from a prospectively collected database of patients who were offered surgical biopsy for mediastinal tumors through either MVATS or standard VATS. Tested outcome measures included feasibility, diagnostic yield, and morbidity. A total of 24 procedures were performed through MVATS. Diagnostic yield was 100%. Median hospital stay and time interval to oncologic treatment were 2 days (IQR, 2-3 days) and 7 days (IQR, 5.5-11.5 days), respectively. At overall comparison (MVATS, N=24 vs. VATS, N=23), there was a significant difference in both frequency and severity of postoperative complication as measured by Clavien-Dindo classification (P<0.006). In a propensity score matched comparison (8 patients per group), grade 3 or 4 complications requiring aggressive management were found only in the general anesthesia group. Global time spent in the operating room was shorter in the MVATS group (P=0.05). Time interval to oncological treatment was the same between groups. Other differences were also found in SIRS score (P=0.05) and PaO 2 /FiO 2 (P=0.04) thus suggesting better adaption to perioperative stress. MVATS biopsy appears to be a reliable tool to optimize diagnostic assessment in patients with mediastinal tumors. It can offer high diagnostic accuracy due to large tissue samples, while reducing morbidity rate compared to the same operation under general anesthesia. More robust evaluation is needed to define the appropriateness of MVATS in this specific clinical setting.

Obtaining spheroplasts of armored dinoflagellates and first single-channel recordings of their ion channels using patch-clamping.

PubMed

Pozdnyakov, Ilya; Matantseva, Olga; Negulyaev, Yuri; Skarlato, Sergei

2014-09-05

Ion channels are tightly involved in various aspects of cell physiology, including cell signaling, proliferation, motility, endo- and exo-cytosis. They may be involved in toxin production and release by marine dinoflagellates, as well as harmful algal bloom proliferation. So far, the patch-clamp technique, which is the most powerful method to study the activity of ion channels, has not been applied to dinoflagellate cells, due to their complex cellulose-containing cell coverings. In this paper, we describe a new approach to overcome this problem, based on the preparation of spheroplasts from armored bloom-forming dinoflagellate Prorocentrum minimum. We treated the cells of P. minimum with a cellulose synthesis inhibitor, 2,6-dichlorobenzonitrile (DCB), and found out that it could also induce ecdysis and arrest cell shape maintenance in these microalgae. Treatment with 100-250 µM DCB led to an acceptable 10% yield of P. minimum spheroplasts and was independent of the incubation time in the range of 1-5 days. We show that such spheroplasts are suitable for patch-clamping in the cell-attached mode and can form 1-10 GOhm patch contact with a glass micropipette, allowing recording of ion channel activity. The first single-channel recordings of dinoflagellate ion channels are presented.

Obtaining Spheroplasts of Armored Dinoflagellates and First Single-Channel Recordings of Their Ion Channels Using Patch-Clamping

PubMed Central

Pozdnyakov, Ilya; Matantseva, Olga; Negulyaev, Yuri; Skarlato, Sergei

2014-01-01

Ion channels are tightly involved in various aspects of cell physiology, including cell signaling, proliferation, motility, endo- and exo-cytosis. They may be involved in toxin production and release by marine dinoflagellates, as well as harmful algal bloom proliferation. So far, the patch-clamp technique, which is the most powerful method to study the activity of ion channels, has not been applied to dinoflagellate cells, due to their complex cellulose-containing cell coverings. In this paper, we describe a new approach to overcome this problem, based on the preparation of spheroplasts from armored bloom-forming dinoflagellate Prorocentrum minimum. We treated the cells of P. minimum with a cellulose synthesis inhibitor, 2,6-dichlorobenzonitrile (DCB), and found out that it could also induce ecdysis and arrest cell shape maintenance in these microalgae. Treatment with 100–250 µM DCB led to an acceptable 10% yield of P. minimum spheroplasts and was independent of the incubation time in the range of 1–5 days. We show that such spheroplasts are suitable for patch-clamping in the cell-attached mode and can form 1–10 GOhm patch contact with a glass micropipette, allowing recording of ion channel activity. The first single-channel recordings of dinoflagellate ion channels are presented. PMID:25199048

Biopsy of Liver Target Lesions under Contrast-Enhanced Ultrasound Guidance - A Multi-Center Study.

PubMed

Francica, Giampiero; Meloni, Maria Franca; de Sio, Ilario; Terracciano, Fulvia; Caturelli, Eugenio; Riccardi, Laura; Roselli, Paola; Iadevaia, Maddalena Diana; Scaglione, Mariano; Lenna, Giovanni; Chiang, Jason; Pompili, Maurizio

2017-12-12

Purpose  To retrospectively characterize the prevalence and impact of contrast-enhanced ultrasound (CEUS) as a guidance technique for the biopsy of liver target lesions (LTLs) at six interventional ultrasound centers. Materials and Methods  The six participating centers retrospectively selected all patients in whom biopsy needles were positioned in LTLs during CEUS. The prevalence of CEUS-guided biopsies at each center between 2005 and 2016, contrast agent consumption, procedure indications, diagnostic yield and complications were assessed. Informed consent was obtained for all patients. Results  CEUS-guided biopsy of LTLs was carried out in 103 patients (68 M/35 F, median age: 69 yrs) with 103 liver target lesions (median size: 20 mm) using cutting needles (18 - 20 g) in 94 cases (91.2 %). CEUS-guided biopsy represented 2.6 % (range: 0.8 - 7.7 %) of 3818 biopsies on LTLs carried out at the participating centers. Indications to CEUS-guided biopsy were: a target lesion not visible on non-enhanced US (27.2 %), improvement of conspicuity of the target (33 %), choice of non-necrotic area inside the target (39.8 %). 26 patients (25.2 %) had a previously non-diagnostic cyto-histological exam. The diagnostic accuracy of the technique was 99 %. No major complications followed infusion of contrast agent or biopsy performance. Conclusion  The indications for CEUS-guided biopsy for LTLs are limited, but CEUS can be useful in challenging clinical scenarios, e. g. poorly visualized or invisible lesions or sampling of non-necrotic areas in the target lesions. There is also a potential advantage in using CEUS to guide repeat biopsies after unsuccessful sampling performed using the standard ultrasound technique. © Georg Thieme Verlag KG Stuttgart · New York.

Design and experimental research of a novel inchworm type piezo-driven rotary actuator with the changeable clamping radius.

PubMed

Zhao, Hongwei; Fu, Lu; Ren, Luquan; Huang, Hu; Fan, Zunqiang; Li, Jianping; Qu, Han

2013-01-01

In this paper, a novel piezo-driven rotary actuator with the changeable clamping radius is developed based on the inchworm principle. This actuator mainly utilizes three piezoelectric actuators, a flexible gripper, a clamping block, and a rotor to achieve large stroke rotation with high resolution. The design process of the flexible gripper consisting of the driving unit and the clamping unit is described. Lever-type mechanisms were used to amplify the micro clamping displacements. The amplifying factor and parasitic displacement of the lever-type mechanism in the clamping unit was analyzed theoretically and experimentally. In order to investigate the rotation characteristics of the actuator, a series of experiments was carried out. Experimental results indicate that the actuator can rotate at a speed of 77,488 μrad/s with a driving frequency of 167 Hz. The rotation resolution and maximum load torque of the actuator are 0.25 μrad and 37 N mm, respectively. The gripper is movable along the z direction based on an elevating platform, and the clamping radius can change from 10.6 mm to 25 mm. Experimental results confirm that the actuator can achieve different rotation speeds by changing the clamping radius.

Magnetic resonance imaging-targeted, 3D transrectal ultrasound-guided fusion biopsy for prostate cancer: Quantifying the impact of needle delivery error on diagnosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, Peter R., E-mail: pmarti46@uwo.ca; Cool, Derek W.; Romagnoli, Cesare

2014-07-15

Purpose: Magnetic resonance imaging (MRI)-targeted, 3D transrectal ultrasound (TRUS)-guided “fusion” prostate biopsy intends to reduce the ∼23% false negative rate of clinical two-dimensional TRUS-guided sextant biopsy. Although it has been reported to double the positive yield, MRI-targeted biopsies continue to yield false negatives. Therefore, the authors propose to investigate how biopsy system needle delivery error affects the probability of sampling each tumor, by accounting for uncertainties due to guidance system error, image registration error, and irregular tumor shapes. Methods: T2-weighted, dynamic contrast-enhanced T1-weighted, and diffusion-weighted prostate MRI and 3D TRUS images were obtained from 49 patients. A radiologist and radiologymore » resident contoured 81 suspicious regions, yielding 3D tumor surfaces that were registered to the 3D TRUS images using an iterative closest point prostate surface-based method to yield 3D binary images of the suspicious regions in the TRUS context. The probabilityP of obtaining a sample of tumor tissue in one biopsy core was calculated by integrating a 3D Gaussian distribution over each suspicious region domain. Next, the authors performed an exhaustive search to determine the maximum root mean squared error (RMSE, in mm) of a biopsy system that gives P ≥ 95% for each tumor sample, and then repeated this procedure for equal-volume spheres corresponding to each tumor sample. Finally, the authors investigated the effect of probe-axis-direction error on measured tumor burden by studying the relationship between the error and estimated percentage of core involvement. Results: Given a 3.5 mm RMSE for contemporary fusion biopsy systems,P ≥ 95% for 21 out of 81 tumors. The authors determined that for a biopsy system with 3.5 mm RMSE, one cannot expect to sample tumors of approximately 1 cm{sup 3} or smaller with 95% probability with only one biopsy core. The predicted maximum RMSE giving P ≥ 95% for

Combined acute hyperglycemic and hyperinsulinemic clamp induced profibrotic and proinflammatory responses in the kidney

PubMed Central

DeSilva, Kristin; Sorice, Gian Pio; Muscogiuri, Giovanna; Jimenez, Fabio; Ahuja, Seema; Barnes, Jefferey L.; Choudhury, Goutam Ghosh; Musi, Nicolas; DeFronzo, Ralph; Kasinath, Balakuntalam S.

2013-01-01

Increase in matrix protein content in the kidney is a cardinal feature of diabetic kidney disease. While renal matrix protein content is increased by chronic hyperglycemia, whether it is regulated by acute elevation of glucose and insulin has not been addressed. In this study, we aimed to evaluate whether short duration of combined hyperglycemia and hyperinsulinemia, mimicking the metabolic environment of prediabetes and early type 2 diabetes, induces kidney injury. Normal rats were subjected to either saline infusion (control, n = 4) or 7 h of combined hyperglycemic-hyperinsulinemic clamp (HG+HI clamp; n = 6). During the clamp, plasma glucose and plasma insulin were maintained at about 350 mg/dl and 16 ng/ml, respectively. HG+HI clamp increased the expression of renal cortical transforming growth factor-β (TGF-β) and renal matrix proteins, laminin and fibronectin. This was associated with the activation of SMAD3, Akt, mammalian target of rapamycin (mTOR) complexes, and ERK signaling pathways and their downstream target events in the initiation and elongation phases of mRNA translation, an important step in protein synthesis. Additionally, HG+HI clamp provoked renal inflammation as shown by the activation of Toll-like receptor 4 (TLR4) and infiltration of CD68-positive monocytes. Urinary F2t isoprostane excretion, an index of renal oxidant stress, was increased in the HG+HI clamp rats. We conclude that even a short duration of hyperglycemia and hyperinsulinemia contributes to activation of pathways that regulate matrix protein synthesis, inflammation, and oxidative stress in the kidney. This finding could have implications for the control of short-term rises in blood glucose in diabetic individuals at risk of developing kidney disease. PMID:24108867

Combined acute hyperglycemic and hyperinsulinemic clamp induced profibrotic and proinflammatory responses in the kidney.

PubMed

Mariappan, Meenalakshmi M; DeSilva, Kristin; Sorice, Gian Pio; Muscogiuri, Giovanna; Jimenez, Fabio; Ahuja, Seema; Barnes, Jefferey L; Choudhury, Goutam Ghosh; Musi, Nicolas; DeFronzo, Ralph; Kasinath, Balakuntalam S

2014-02-01

Increase in matrix protein content in the kidney is a cardinal feature of diabetic kidney disease. While renal matrix protein content is increased by chronic hyperglycemia, whether it is regulated by acute elevation of glucose and insulin has not been addressed. In this study, we aimed to evaluate whether short duration of combined hyperglycemia and hyperinsulinemia, mimicking the metabolic environment of prediabetes and early type 2 diabetes, induces kidney injury. Normal rats were subjected to either saline infusion (control, n = 4) or 7 h of combined hyperglycemic-hyperinsulinemic clamp (HG+HI clamp; n = 6). During the clamp, plasma glucose and plasma insulin were maintained at about 350 mg/dl and 16 ng/ml, respectively. HG+HI clamp increased the expression of renal cortical transforming growth factor-β (TGF-β) and renal matrix proteins, laminin and fibronectin. This was associated with the activation of SMAD3, Akt, mammalian target of rapamycin (mTOR) complexes, and ERK signaling pathways and their downstream target events in the initiation and elongation phases of mRNA translation, an important step in protein synthesis. Additionally, HG+HI clamp provoked renal inflammation as shown by the activation of Toll-like receptor 4 (TLR4) and infiltration of CD68-positive monocytes. Urinary F2t isoprostane excretion, an index of renal oxidant stress, was increased in the HG+HI clamp rats. We conclude that even a short duration of hyperglycemia and hyperinsulinemia contributes to activation of pathways that regulate matrix protein synthesis, inflammation, and oxidative stress in the kidney. This finding could have implications for the control of short-term rises in blood glucose in diabetic individuals at risk of developing kidney disease.

Protein associations in DnaA-ATP hydrolysis mediated by the Hda-replicase clamp complex.

PubMed

Su'etsugu, Masayuki; Shimuta, Toh-Ru; Ishida, Takuma; Kawakami, Hironori; Katayama, Tsutomu

2005-02-25

In Escherichia coli, the activity of ATP-bound DnaA protein in initiating chromosomal replication is negatively controlled in a replication-coordinated manner. The RIDA (regulatory inactivation of DnaA) system promotes DnaA-ATP hydrolysis to produce the inactivated form DnaA-ADP in a manner depending on the Hda protein and the DNA-loaded form of the beta-sliding clamp, a subunit of the replicase holoenzyme. A highly functional form of Hda was purified and shown to form a homodimer in solution, and two Hda dimers were found to associate with a single clamp molecule. Purified mutant Hda proteins were used in a staged in vitro RIDA system followed by a pull-down assay to show that Hda-clamp binding is a prerequisite for DnaA-ATP hydrolysis and that binding is mediated by an Hda N-terminal motif. Arg(168) in the AAA(+) Box VII motif of Hda plays a role in stable homodimer formation and in DnaA-ATP hydrolysis, but not in clamp binding. Furthermore, the DnaA N-terminal domain is required for the functional interaction of DnaA with the Hda-clamp complex. Single cells contain approximately 50 Hda dimers, consistent with the results of in vitro experiments. These findings and the features of AAA(+) proteins, including DnaA, suggest the following model. DnaA-ATP is hydrolyzed at a binding interface between the AAA(+) domains of DnaA and Hda; the DnaA N-terminal domain supports this interaction; and the interaction of DnaA-ATP with the Hda-clamp complex occurs in a catalytic mode.

Ultrasound-guided fine needle aspiration versus core needle biopsy: comparison of post-biopsy hematoma rates and risk factors.

PubMed

Chae, In Hye; Kim, Eun-Kyung; Moon, Hee Jung; Yoon, Jung Hyun; Park, Vivian Y; Kwak, Jin Young

2017-07-01

To compare post-biopsy hematoma rates between ultrasound guided-fine needle aspiration and ultrasound guided-core needle biopsy, and to investigate risk factors for post-biopsy hematoma. A total of 5304 thyroid nodules which underwent ultrasound guided biopsy were included in this retrospective study. We compared clinical and US features between patients with and without post-biopsy hematoma. Associations between these features and post-biopsy hematoma were analyzed. Post-biopsy hematoma rate was 0.8% (43/5121) for ultrasound guided-fine needle aspiration and 4.9% (9/183) for ultrasound guided-core needle biopsy (P < 0.001). For ultrasound guided-fine needle aspiration, gender, age, size, presence of vascularity, and suspicious US features were not associated with post-biopsy hematoma according to experience level. Post-biopsy hematoma occurred significantly more with ultrasound guided-core needle biopsy (9/179, 5.0%) than with ultrasound guided-fine needle aspiration (9/1138, 0.8%) (P < 0.001) in experienced performers and ultrasound guided-core needle biopsy was the only significant risk factor for post-biopsy hematoma (adjusted Odds Ratio, 6.458, P < 0.001). Post-biopsy hematoma occurred significantly more in ultrasound guided-core needle biopsy than in ultrasound guided-fine needle aspiration and ultrasound guided-core needle biopsy was the only independent factor of post-biopsy hematoma in thyroid nodules.

Comparison of Stereotactic and Ultrasound-guided Biopsy of Solid Supratentorial Tumor: A Preliminary Report

PubMed Central

Satyarthee, Guru Dutta; Chandra, P. Sarat; Sharma, Bhawani S.; Mehta, V. S.

2017-01-01

Introduction: The computed tomography (CT) guided stereotactic biopsy (STB) is considered as method of choice for biopsy of intracranial mass lesions. However, it's disadvantages are frame fixation, time requirement for transportation between CT scan suit to the operation theater with added much higher equipment cost in the relatively resource scarred developing country. Ultrasound-guided biopsy (USGB) is relatively simpler, economical, less time consuming, and real-time procedure. Clinical Materials and Methods: Thirty-seven consecutively admitted patients with supratentorial brain tumors, who underwent biopsy of the lesion using CT compatible stereotactic and ultrasound-guided (USGB) procedure formed cohort of the study. Based on location and size of the lesions, the cases were divided into two groups, superficial and deep. Twenty-two patients underwent ultrasound-guided biopsy and 15 with STB. Results: The diagnostic yield of STB was 93% and 91% for ultrasound-guided biopsy. The mean operation time of STB group was 149.00 min and 94 min for USGB, which was statistically significant. Two cases in each group developed hematoma; however, one case in USGB group needed surgical evacuation. The real-time monitoring detected two hematoma intraoperatively, which were further also confirmed on postoperative CT scan head. Conclusions: The ultrasound-guided biopsy procedure (USGB) was simple, relatively shorter time-consuming procedure and equally efficacious and utilizing economical equipment and can act as a safer alternative to CT STB process for biopsy of the intracranial mass lesion. Furthermore, USGB also provided intra-operative real-time monitoring, which provided clue for close monitoring in the postoperative period after completion of biopsy to look for development of fresh hematoma development not only at the biopsy site but also along the biopsy track and adjoining area. Perhaps, a longer period of ultrasonic monitoring following the procedure would be of

Percutaneous Biopsy of Osteoid Osteomas Prior to Percutaneous Treatment Using Two Different Biopsy Needles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laredo, Jean-Denis, E-mail: jean-denis.laredo@lrb.aphp.fr; Hamze, Bassam; Jeribi, Riadh

2009-09-15

Biopsy is usually performed as the first step in percutaneous treatment of osteoid osteomas prior to laser photocoagulation. At our institution, 117 patients with a presumed diagnosis of osteoid osteoma had a trephine biopsy before a percutaneous laser photocoagulation. Biopsies were made using two different types of needles. A Bonopty biopsy needle (14-gauge cannula, 16-gauge trephine needle; Radi Medical Systems, Uppsala, Sweden) was used in 65 patients, and a Laurane biopsy needle (11-gauge cannula, 12.5-gauge trephine needle; Laurane Medical, Saint-Arnoult, France) in 43 patients. Overall biopsy results were positive for osteoid osteoma in 83 (70.9%) of the 117 cases. Themore » Laurane needle provided a significantly higher positive rate (81.4%) than the Bonopty needle (66.1%; p < 0.05). This difference was not due to the size of the nidus, which was similar in the two groups (p < 0.05) and may be an effect of differences in needle caliber (12.5 vs. 14 gauge) as well as differences in needle design. The rate of positive biopsy results obtained in the present series with the Laurane biopsy needle is, to our knowledge, the highest rate reported in series dealing with percutaneous radiofrequency ablation and laser photocoagulation of osteoid osteomas.« less

Spectrum of intra-thoracic lesion detected by computed tomography guided fine needle aspiration biopsy.

PubMed

Naqvi, Hanna; Edhi, Muhammad Muzzammil; Aslam, Hafiz Muhammad; Faridi, Naveen

2013-02-12

Fine needle aspiration biopsy (FNAB) is a rapid, sensitive and inexpensive procedure for diagnosing benign and malignant palpable lesions. For lesions that are not palpable or deep seated, FNAB can be performed under the guidance of radiological imaging. Our basic objective was to evaluate the spectrum of intrathoracic lesions by using Computed Tomography guided fine needle aspiration biopsy and evaluate its diagnostic yield. It was a retrospective study carried out in the Department of Histopathology, Liaquat National Hospital and Medical College, during the months of August 2011 and August 2012. All patients with pulmonary, mediastinal or paravertebral mass who underwent CT guided intrathoracic biopsy were included in this study. Fine needle aspiration biopsies were performed in the Radiology Department and specimen retrieved was sent in 10% buffered Formalin to the Histopathology Department. All the data was entered and analyzed through SPSS 19.0. A total of 130 cases were evaluated, out of which 108 (83.1%) were pulmonary, 16 (12.3%) were mediastinal and 6 (4.6%) were paravertebral. Conclusive biopsies were possible in 113 cases, while 17 biopsies were inconclusive. In those that showed a conclusive diagnosis, 83.1% were neoplastic and 16.9% were non neoplastic. Of the neoplastic cases, 27 (20.8%) were adenocarcinomas, followed by squamous cell carcinomas (15.4%) and large cell carcinoma, not otherwise specified, (12.3%). CT guided fine needle aspiration biopsy is a reliable tool for examination of intrathoracic lesions, with a high rate of conclusive diagnosis.

30 CFR 18.40 - Cable clamps and grips.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable clamps and grips. 18.40 Section 18.40 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design...

Combination of prostate imaging reporting and data system (PI-RADS) score and prostate-specific antigen (PSA) density predicts biopsy outcome in prostate biopsy naïve patients.

PubMed

Washino, Satoshi; Okochi, Tomohisa; Saito, Kimitoshi; Konishi, Tsuzumi; Hirai, Masaru; Kobayashi, Yutaka; Miyagawa, Tomoaki

2017-02-01

-RADS v2 score of ≤3 and PSA density of <0.15 ng/mL/mL yielded no clinically significant prostate cancer and no additional detection of prostate cancer on further biopsies. A combination of PI-RADS v2 score and PSA density can help in the decision-making process before prostate biopsy and in the follow-up strategy in biopsy naïve patients. Patients with a PI-RADS v2 score of ≤3 and PSA density of <0.15 ng/mL/mL may avoid unnecessary biopsies. © 2016 The Authors BJU International published by John Wiley & Sons Ltd on behalf of BJU International.

33 CFR 183.532 - Clips, straps, and hose clamps.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Equipment Standards § 183.532 Clips... under § 183.590, a hose clamp installed on a fuel line system requiring metallic fuel lines or “USCG...

Role of the α clamp in the protein translocation mechanism of anthrax toxin

PubMed Central

Brown, Michael J.; Thoren, Katie L.; Krantz, Bryan A.

2015-01-01

Membrane-embedded molecular machines are utilized to move water-soluble proteins across these barriers. Anthrax toxin forms one such machine through the self-assembly of its three component proteins—protective antigen (PA), lethal factor (LF), and edema factor (EF). Upon endocytosis into host cells, acidification of the endosome induces PA to form a membrane-inserted channel, which unfolds LF and EF and translocates them into the host cytosol. Translocation is driven by the proton motive force, comprised of the chemical potential, the proton-gradient (ΔpH), and the membrane potential (ΔΨ). A crystal structure of the lethal toxin core complex revealed an “α clamp” structure that binds to substrate helices nonspecifically. Here we test the hypothesis that through the recognition of unfolding helical structure the α clamp can accelerate the rate of translocation. We produced a synthetic PA mutant in which an α helix was crosslinked into the α clamp to block its function. This synthetic construct impairs translocation by raising a yet uncharacterized translocation barrier shown to be much less force dependent than the known unfolding barrier. We also report that the α clamp more stably binds substrates that can form helices than those, such as polyproline, that cannot. Hence the α clamp recognizes substrates by a general shape-complementarity mechanism. Substrates that are incapable of forming compact secondary structure (due to the introduction of a polyproline track) are severely deficient for translocation. Therefore, the α clamp and its recognition of helical structure in the translocating substrate play key roles in the molecular mechanism of protein translocation. PMID:26344833

Thermodynamic basis for engineering high-affinity, high-specificity binding-induced DNA clamp nanoswitches.

PubMed

Idili, Andrea; Plaxco, Kevin W; Vallée-Bélisle, Alexis; Ricci, Francesco

2013-12-23

Naturally occurring chemoreceptors almost invariably employ structure-switching mechanisms, an observation that has inspired the use of biomolecular switches in a wide range of artificial technologies in the areas of diagnostics, imaging, and synthetic biology. In one mechanism for generating such behavior, clamp-based switching, binding occurs via the clamplike embrace of two recognition elements onto a single target molecule. In addition to coupling recognition with a large conformational change, this mechanism offers a second advantage: it improves both affinity and specificity simultaneously. To explore the physics of such switches we have dissected here the thermodynamics of a clamp-switch that recognizes a target DNA sequence through both Watson-Crick base pairing and triplex-forming Hoogsteen interactions. When compared to the equivalent linear DNA probe (which relies solely on Watson-Crick interactions), the extra Hoogsteen interactions in the DNA clamp-switch increase the probe's affinity for its target by ∼0.29 ± 0.02 kcal/mol/base. The Hoogsteen interactions of the clamp-switch likewise provide an additional specificity check that increases the discrimination efficiency toward a single-base mismatch by 1.2 ± 0.2 kcal/mol. This, in turn, leads to a 10-fold improvement in the width of the "specificity window" of this probe relative to that of the equivalent linear probe. Given these attributes, clamp-switches should be of utility not only for sensing applications but also, in the specific field of DNA nanotechnology, for applications calling for a better control over the building of nanostructures and nanomachines.

MATLAB implementation of a dynamic clamp with bandwidth >125 KHz capable of generating INa at 37°C

PubMed Central

Clausen, Chris; Valiunas, Virginijus; Brink, Peter R.; Cohen, Ira S.

2012-01-01

We describe the construction of a dynamic clamp with bandwidth >125 KHz that utilizes a high performance, yet low cost, standard home/office PC interfaced with a high-speed (16 bit) data acquisition module. High bandwidth is achieved by exploiting recently available software advances (code-generation technology, optimized real-time kernel). Dynamic-clamp programs are constructed using Simulink, a visual programming language. Blocks for computation of membrane currents are written in the high-level matlab language; no programming in C is required. The instrument can be used in single- or dual-cell configurations, with the capability to modify programs while experiments are in progress. We describe an algorithm for computing the fast transient Na+ current (INa) in real time, and test its accuracy and stability using rate constants appropriate for 37°C. We then construct a program capable of supplying three currents to a cell preparation: INa, the hyperpolarizing-activated inward pacemaker current (If), and an inward-rectifier K+ current (IK1). The program corrects for the IR drop due to electrode current flow, and also records all voltages and currents. We tested this program on dual patch-clamped HEK293 cells where the dynamic clamp controls a current-clamp amplifier and a voltage-clamp amplifier controls membrane potential, and current-clamped HEK293 cells where the dynamic clamp produces spontaneous pacing behavior exhibiting Na+ spikes in otherwise passive cells. PMID:23224681

3T MR-guided in-bore transperineal prostate biopsy: A comparison of robotic and manual needle-guidance templates.

PubMed

Tilak, Gaurie; Tuncali, Kemal; Song, Sang-Eun; Tokuda, Junichi; Olubiyi, Olutayo; Fennessy, Fiona; Fedorov, Andriy; Penzkofer, Tobias; Tempany, Clare; Hata, Nobuhiko

2015-07-01

To demonstrate the utility of a robotic needle-guidance template device as compared to a manual template for in-bore 3T transperineal magnetic resonance imaging (MRI)-guided prostate biopsy. This two-arm mixed retrospective-prospective study included 99 cases of targeted transperineal prostate biopsies. The biopsy needles were aimed at suspicious foci noted on multiparametric 3T MRI using manual template (historical control) as compared with a robotic template. The following data were obtained: the accuracy of average and closest needle placement to the focus, histologic yield, percentage of cancer volume in positive core samples, complication rate, and time to complete the procedure. In all, 56 cases were performed using the manual template and 43 cases were performed using the robotic template. The mean accuracy of the best needle placement attempt was higher in the robotic group (2.39 mm) than the manual group (3.71 mm, P < 0.027). The mean core procedure time was shorter in the robotic (90.82 min) than the manual group (100.63 min, P < 0.030). Percentage of cancer volume in positive core samples was higher in the robotic group (P < 0.001). Cancer yields and complication rates were not statistically different between the two subgroups (P = 0.557 and P = 0.172, respectively). The robotic needle-guidance template helps accurate placement of biopsy needles in MRI-guided core biopsy of prostate cancer. © 2014 Wiley Periodicals, Inc.

Reversible fastener clamp load monitor with continuous visual or remote readout

NASA Astrophysics Data System (ADS)

Hodge, Malcolm H.; Kausel, Theodore C., Jr.; Begley, Matthew R.

1998-03-01

SIMS has developed a simple means for detecting and monitoring both absolute and relative clamp load, or bolt tension, in fastener systems. More than twenty-five percent of automotive failures are known to be due to undetected loss of fastener clamp load. While the equivalent aerospace maintenance statistics are not known, the average automobile has 3,500 fasteners while a Boeing 747 has closer to one million. It is therefore anticipated that the new SensaBolt clamp load tracking system could find wide applications in the aerospace arena. We describe a visually-evident and retrofitted clamp load monitoring design which is based on the differential joint substrate compression at, and immediately adjacent to, the fastener location. This intrinsically-accurate indicator does not necessarily require alteration in either the bolt or nut geometries, thereby facilitating product introduction and retrofit in aging aircraft applications. In addition, SensaBolt's sole reliance on substrate compression renders it more accurate then torque wrench or turn-of-nut techniques. Readout may be accomplished by any of three principal methods: for those applications with ease of access to the sensor, loss of tension can be determined by direct visual inspection. Application of a standard wrench can then be made to restore the fastener's proper tightness, per the SensaBolt indicators. In those instances where line-of-sight is unimpeded and more formal inspection is desired, the SensaBolt may be interrogated by a laser scanner bar code reader. Finally, SensaBolt may be addressed by the SIMS fiber optic harness for those instances where full-time remote interrogation is desired.

Non-Arcing Clamp for Automotive Battery Jumper Cables.

DTIC Science & Technology

cable via an encapsulated pressure switch . The pressure switch is physically positioned between the copper jaw and the jaw end of the gripping member...such that spring pressure provided by the torsion spring is operative for closing the pressure switch when the clamp is mounted on a battery terminal

Theoretical investigation of gain-clamped semiconductor optical amplifiers using the amplified spontaneous emission compensating effect

NASA Astrophysics Data System (ADS)

Jia, Xin-Hong

2006-12-01

The theoretical model on gain-clamped semiconductor optical amplifiers (GC-SOAs) based on compensating light has been constructed. Using this model, the effects of insertion position and peak reflectivity of the fiber Bragg grating (FBG) on the gain clamping and noise figure (NF) characteristics of GC-SOA are analyzed. The results show that the effect of the FBG insertion position on gain clamping is slight, but the lower NF can be obtained for input FBG-type GC-SOA; when the FBG peak wavelength is designed to close the signal wavelength, the gain clamping and NF characteristics that can be reached are better. Further study shows that, with the increased peak reflectivity of the FBG, the critical input power is broadened and the gain tends to be varied slowly; the larger bias current is helpful to raise gain and decrease the noise figure but is harmful to a gain flatness characteristic.

Stereotactic (Mammographically Guided) Breast Biopsy

MedlinePlus

... the type of biopsy being performed or the design of the biopsy machine, a biopsy of tissue ... cost information. The costs for specific medical imaging tests, treatments and procedures may vary by geographic region. ...

Crystal structure of the DNA polymerase III β subunit (β-clamp) from the extremophile Deinococcus radiodurans.

PubMed

Niiranen, Laila; Lian, Kjersti; Johnson, Kenneth A; Moe, Elin

2015-02-27

Deinococcus radiodurans is an extremely radiation and desiccation resistant bacterium which can tolerate radiation doses up to 5,000 Grays without losing viability. We are studying the role of DNA repair and replication proteins for this unusual phenotype by a structural biology approach. The DNA polymerase III β subunit (β-clamp) acts as a sliding clamp on DNA, promoting the binding and processivity of many DNA-acting proteins, and here we report the crystal structure of D. radiodurans β-clamp (Drβ-clamp) at 2.0 Å resolution. The sequence verification process revealed that at the time of the study the gene encoding Drβ-clamp was wrongly annotated in the genome database, encoding a protein of 393 instead of 362 amino acids. The short protein was successfully expressed, purified and used for crystallisation purposes in complex with Cy5-labeled DNA. The structure, which was obtained from blue crystals, shows a typical ring-shaped bacterial β-clamp formed of two monomers, each with three domains of identical topology, but with no visible DNA in electron density. A visualisation of the electrostatic surface potential reveals a highly negatively charged outer surface while the inner surface and the dimer forming interface have a more even charge distribution. The structure of Drβ-clamp was determined to 2.0 Å resolution and shows an evenly distributed electrostatic surface charge on the DNA interacting side. We hypothesise that this charge distribution may facilitate efficient movement on encircled DNA and help ensure efficient DNA metabolism in D. radiodurans upon exposure to high doses of ionizing irradiation or desiccation.

Comparative cost-effectiveness of fine needle aspiration biopsy versus image-guided biopsy, and open surgical biopsy in the evaluation of breast cancer in the era of Affordable Care Act: a changing landscape.

PubMed

Masood, Shahla; Rosa, Marilin; Kraemer, Dale F; Smotherman, Carmen; Mohammadi, Amir

2015-08-01

Proven as a time challenged and cost-effective sampling procedure, the use of FNAB has still remained controversial among the scientific community. Currently, other minimally invasive sampling procedures such as ultrasound guided fine needle aspiration biopsy (US-FNAB) and image guided core needle biopsy (IG-CNB) have become the preferred sampling procedures for evaluation of breast lesions. However, changes in the medical economy and the current growing emphasis on cost containment in the era of the Affordable Care Act make it necessary to stimulate a renewed interest in the use of FNAB as the initial diagnostic sampling procedure. This study was designed to define the changing trend in the practice of tissue sampling during the last several years, and to assess the comparative effectiveness and appropriateness of the procedure of choice for breast cancer diagnosis. After Institutional Review Board (IRB) approval, the computer database of the Pathology Department, University of Florida, College of Medicine-Jacksonville at UF Health was retrospectively searched to identify all breast biopsy pathology reports issued during the period of January 2004 to December 2011. The inclusion criteria were all women that underwent any of the following biopsy types: FNAB, US-FNAB, IG-CNB, and surgical biopsy (SB). Diagnostic procedures were identified using current procedural terminology (CPT) codes recorded on claims from the UF Health Jacksonville patient accounting application files. The data obtained was used to determine which technique has the best cost-effectiveness in the diagnosis of breast cancer. The outcome variable for this project was a positive breast cancer diagnosis resulting from these methodologies. The predictor variable was the biopsy type used for sampling. The rate of cancer detection for each procedure was also determined. Among the four groups of procedures compared, the lower cost was attributed to FNAB, followed by US-FNAB, and SB. IG-CNB was the most

The RNA polymerase clamp interconverts dynamically among three states and is stabilized in a partly closed state by ppGpp.

PubMed

Duchi, Diego; Mazumder, Abhishek; Malinen, Anssi M; Ebright, Richard H; Kapanidis, Achillefs N

2018-06-06

RNA polymerase (RNAP) contains a mobile structural module, the 'clamp,' that forms one wall of the RNAP active-center cleft and that has been linked to crucial aspects of the transcription cycle, including promoter melting, transcription elongation complex stability, transcription pausing, and transcription termination. Using single-molecule FRET on surface-immobilized RNAP molecules, we show that the clamp in RNAP holoenzyme populates three distinct conformational states and interconvert between these states on the 0.1-1 s time-scale. Similar studies confirm that the RNAP clamp is closed in open complex (RPO) and in initial transcribing complexes (RPITC), including paused initial transcribing complexes, and show that, in these complexes, the clamp does not exhibit dynamic behaviour. We also show that, the stringent-response alarmone ppGpp, which reprograms transcription during amino acid starvation stress, selectively stabilizes the partly-closed-clamp state and prevents clamp opening; these results raise the possibility that ppGpp controls promoter opening by modulating clamp dynamics.

Molecular image-directed biopsies: improving clinical biopsy selection in patients with multiple tumors

NASA Astrophysics Data System (ADS)

Harmon, Stephanie A.; Tuite, Michael J.; Jeraj, Robert

2016-10-01

Site selection for image-guided biopsies in patients with multiple lesions is typically based on clinical feasibility and physician preference. This study outlines the development of a selection algorithm that, in addition to clinical requirements, incorporates quantitative imaging data for automatic identification of candidate lesions for biopsy. The algorithm is designed to rank potential targets by maximizing a lesion-specific score, incorporating various criteria separated into two categories: (1) physician-feasibility category including physician-preferred lesion location and absolute volume scores, and (2) imaging-based category including various modality and application-specific metrics. This platform was benchmarked in two clinical scenarios, a pre-treatment setting and response-based setting using imaging from metastatic prostate cancer patients with high disease burden (multiple lesions) undergoing conventional treatment and receiving whole-body [18F]NaF PET/CT scans pre- and mid-treatment. Targeting of metastatic lesions was robust to different weighting ratios and candidacy for biopsy was physician confirmed. Lesion ranked as top targets for biopsy remained so for all patients in pre-treatment and post-treatment biopsy selection after sensitivity testing was completed for physician-biased or imaging-biased scenarios. After identifying candidates, biopsy feasibility was evaluated by a physician and confirmed for 90% (32/36) of high-ranking lesions, of which all top choices were confirmed. The remaining cases represented lesions with high anatomical difficulty for targeting, such as proximity to sciatic nerve. This newly developed selection method was successfully used to quantitatively identify candidate lesions for biopsies in patients with multiple lesions. In a prospective study, we were able to successfully plan, develop, and implement this technique for the selection of a pre-treatment biopsy location.

Glomerular loss after arteriovenous and arterial clamping for renal warm ischemia in a swine model.

PubMed

Bechara, Gustavo Ruschi; Damasceno-Ferreira, José Aurelino; Abreu, Leonardo Albuquerque Dos Santos; Costa, Waldemar Silva; Sampaio, Francisco José Barcellos; Pereira-Sampaio, Marco Aurélio; Souza, Diogo Benchimol De

2016-11-01

To evaluate the glomerular loss after arteriovenous or arterial warm ischemia in a swine model. Twenty four pigs were divided into Group Sham (submitted to all surgical steps except the renal ischemia), Group AV (submitted to 30 minutes of warm ischemia by arteriovenous clamping of left kidney vessels), and Group A (submitted to 30 minutes of ischemia by arterial clamping). Right kidneys were used as controls. Weigh, volume, cortical volume, glomerular volumetric density (Vv[Glom]), volume-weighted glomerular volume (VWGV), and the total number of glomeruli were measured for each organ. Group AV showed a 24.5% reduction in its left kidney Vv[Glom] and a 25.4% reduction in the VWGV, when compared to the right kidney. Reductions were also observed when compared to kidneys of sham group. There was a reduction of 19.2% in the total number of glomeruli in AV kidneys. No difference was observed in any parameters analyzed on the left kidneys from group A. Renal warm ischemia of 30 minutes by arterial clamping did not caused significant glomerular damage, but arteriovenous clamping caused significant glomerular loss in a swine model. Clamping only the renal artery should be considered to minimize renal injury after partial nephrectomies.

Gram stain of tissue biopsy

MedlinePlus

... biopsy To use the sharing features on this page, please enable JavaScript. Gram stain of tissue biopsy test involves using crystal violet stain to test a sample of tissue taken from a biopsy . The Gram stain method can ...

Industrializing electrophysiology: HT automated patch clamp on SyncroPatch® 96 using instant frozen cells.

PubMed

Polonchuk, Liudmila

2014-01-01

Patch-clamping is a powerful technique for investigating the ion channel function and regulation. However, its low throughput hampered profiling of large compound series in early drug development. Fortunately, automation has revolutionized the area of experimental electrophysiology over the past decade. Whereas the first automated patch-clamp instruments using the planar patch-clamp technology demonstrated rather a moderate throughput, few second-generation automated platforms recently launched by various companies have significantly increased ability to form a high number of high-resistance seals. Among them is SyncroPatch(®) 96 (Nanion Technologies GmbH, Munich, Germany), a fully automated giga-seal patch-clamp system with the highest throughput on the market. By recording from up to 96 cells simultaneously, the SyncroPatch(®) 96 allows to substantially increase throughput without compromising data quality. This chapter describes features of the innovative automated electrophysiology system and protocols used for a successful transfer of the established hERG assay to this high-throughput automated platform.

Recutting prostate needle core biopsies with high grade prostatic intraepithelial neoplasia increases detection of adenocarcinoma.

PubMed

Rapp, David E; Msezane, Lambda P; Reynolds, W Stuart; Lotan, Tamara L; Obara, Piotr; O'Connor, R Corey; Taxy, Jerome B; Gerber, Glenn S; Zagaja, Gregory P

2009-02-01

We sought to evaluate the ability of biopsy core recutting to increase cancer detection in patients with high grade prostatic intraepithelial neoplasia (HGPIN). This prospective study encompasses all patients undergoing 12 core TRUS guided prostate biopsy between February 2004 and January 2007. In patients with HGPIN on initial biopsy, the paraffin blocks were resampled for cancer by additional deeper levels per core. Additional analysis was performed in the patients with HGPIN in order to detect whether significant differences in prebiopsy variables were associated with patients subsequently found to have benign versus carcinoma on recutting. Last, the costs associated with this procedure were studied. Forty of 584 (6.8%) patients undergoing prostate biopsy were found to have HGPIN in the absence of prostatic adenocarcinoma on initial histopathology. Following recutting, 12.5% (5/40) of these patients were found to have prostatic adenocarcinoma not previously detected. Of the remaining 35 patients, 18 underwent repeat biopsy. Of these, five patients were found to have adenocarcinoma and three were found to have persistent HGPIN. The PSA, PSA density (PSAD), and PSA velocity (PSAV) prior to initial biopsy were not statistically different when comparing patients found to have benign tissue versus carcinoma on recutting. In patients with HGPIN, at our institution, recutting the biopsy would yield a cost savings of $436/patient as opposed to universal rebiopsy. Our data suggest that prostate biopsy recutting may increase cancer detection in patients initially found to have HGPIN. Additionally, a significant cost savings is associated with the recutting protocol.

[Focus on placental transfusion for preterm neonates: Delayed cord clamping and/or milking?

PubMed

Sorin, G; Tosello, B

2016-11-01

Anemia of prematurity remains a common complication despite recent advances in perinatal and neonatal medicine. The delayed cord clamping (at least 30seconds as recommended) has several benefits: increased hemoglobin and hematocrit levels at birth, improved initial hemodynamic, decreased incidence of transfusions and intraventricular hemorrhages. When the birth transition is difficult, wait 30seconds before clamping can be impossible. So as not to interfere with the neonatal resuscitation, the "milking" has been proposed as an alternative method to the delayed cord clamping. This is a safe and easy method, which can be done either by an obstetrician or pediatrician with comparable results for the child on his hemodynamic, hematological and neurological status. It still lacks technical information on this method and neurodevelopmental outcomes of these preterm infants. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Spectrum of intra-thoracic lesion detected by computed tomography guided fine needle aspiration biopsy

PubMed Central

2013-01-01

Background Fine needle aspiration biopsy (FNAB) is a rapid, sensitive and inexpensive procedure for diagnosing benign and malignant palpable lesions. For lesions that are not palpable or deep seated, FNAB can be performed under the guidance of radiological imaging. Our basic objective was to evaluate the spectrum of intrathoracic lesions by using Computed Tomography guided fine needle aspiration biopsy and evaluate its diagnostic yield. Methodology It was a retrospective study carried out in the Department of Histopathology, Liaquat National Hospital and Medical College, during the months of August 2011 and August 2012. All patients with pulmonary, mediastinal or paravertebral mass who underwent CT guided intrathoracic biopsy were included in this study. Fine needle aspiration biopsies were performed in the Radiology Department and specimen retrieved was sent in 10% buffered Formalin to the Histopathology Department. All the data was entered and analyzed through SPSS 19.0. Results A total of 130 cases were evaluated, out of which 108 (83.1%) were pulmonary, 16 (12.3%) were mediastinal and 6 (4.6%) were paravertebral. Conclusive biopsies were possible in 113 cases, while 17 biopsies were inconclusive. In those that showed a conclusive diagnosis, 83.1% were neoplastic and 16.9% were non neoplastic. Of the neoplastic cases, 27 (20.8%) were adenocarcinomas, followed by squamous cell carcinomas (15.4%) and large cell carcinoma, not otherwise specified, (12.3%). Conclusion CT guided fine needle aspiration biopsy is a reliable tool for examination of intrathoracic lesions, with a high rate of conclusive diagnosis. PMID:23402220

Real-time intraprocedural 18F-FDG PET/CT-guided biopsy using automated robopsy arm (ARA) in the diagnostic evaluation of thoracic lesions with prior inconclusive biopsy results: initial experience from a tertiary health care centre.

PubMed

Radhakrishnan, Renjith Kalathoorakathu; Mittal, Bhagwant Rai; Gorla, Arun Kumar Reddy; Basher, Rajender Kumar; Sood, Ashwani; Bal, Amanjit; Kalra, Naveen; Khandelwal, Niranjan; Singh, Navneet; Behera, Digambar

2017-12-01

The aim of this study was to assess the feasibility and appraise the diagnostic utility of real time 18 F-FDG PET/CT-guided biopsy under automated robopsy arm (ARA) guidance for the evaluation of thoracic lesions with prior inconclusive biopsy results. PET/CT-guided biopsy of thoracic lesions was performed in patients who had at least one previous inconclusive biopsy. A total of 25 patients (male:female-18 males, 7 females; age: range, 13-75; mean, 53.7) were included in this study. All these patients underwent percutaneous needle biopsies under real-time PET/CT guidance using ARA (ROBIO-EX, Perfint healthcare Pvt Ltd, Chennai, India) needle navigation technique. Histopathology and clinical follow-up results were reviewed for assessing the accuracy of procedures. Adequate representative tissue sample could be retrieved in all the patients. No major procedure-related complications were encountered in any patient. Of the 25 procedures, 21 lesions were positive for malignancy and benign findings were observed in the other 4 lesions on histopathology. None of the patients required further biopsy in arriving at a final diagnosis. Overall diagnostic yield of the procedure was 100%. Real time 18 F-FDG PET/CT guidance for percutaneous biopsies of lung and mediastinal lesions is a feasible technique with potential utility in patients with previous inconclusive biopsy results. Advances in knowledge: 18 F-FDG PET/CT guidance reduces the sampling errors by specifically targeting areas of viability and avoiding necrosis/atelectasis. A navigational tool like ARA is thought to help in accurately targeting these areas.

CT-guided transgluteal biopsy for systematic sampling of the prostate in patients without rectal access: a 13-year single-center experience.

PubMed

Olson, Michael C; Atwell, Thomas D; Mynderse, Lance A; King, Bernard F; Welch, Timothy; Goenka, Ajit H

2017-08-01

The purpose of our study was to examine the safety and diagnostic utility of transgluteal CT-guided prostate biopsy for prostate sampling in patients without rectal access. Seventy-three biopsies were performed in 65 patients over a 13-year period (2002-2015). Mean prostate-specific antigen (PSA) at biopsy was 7.8 ng/mL (range 0.37-31.5). Electronic medical records were reviewed for procedural details and complications. Mean PSA and number of cores in malignant and benign cohorts were compared with Student's t test. Technical success rate was 97.3% (71/73; mean cores 8, range 3-28). Of these, 43.6% (31/71) yielded malignancy (mean Gleason score 7, range 6-10) and 56.3% (40/71) yielded benign tissue. The only complication was an asymptomatic periprostatic hematoma (1/73; 1.4%). In 14 patients who underwent surgery, Gleason scores were concordant in 71.4% (10/14) and discordant in 28.6% (4/14; Gleason 6 on biopsy but Gleason 7 on surgical specimen). Mean effective radiation dose was 18.5 mSv (median 15.0, range 4.4-86.2). There was no significant difference in either mean PSA (p = 0.06) or number of core specimens (p = 0.33) between malignant and benign cohorts. CT-guided transgluteal prostate biopsy is highly safe and reliable for the detection of prostate cancer in men without rectal access. • Prostate cancer detection in men without rectal access is challenging. • CT-guided transgluteal prostate biopsy is safe and effective in these patients. • CT-guided biopsy may be particularly effective in diagnosing high-grade prostate cancer. • Unilateral CT-guided biopsy may be effective in patients with focal lesions. • The radiation exposure with this technique is acceptable.

Clamped seismic metamaterials: ultra-low frequency stop bands

NASA Astrophysics Data System (ADS)

Achaoui, Y.; Antonakakis, T.; Brûlé, S.; Craster, R. V.; Enoch, S.; Guenneau, S.

2017-06-01

The regularity of earthquakes, their destructive power, and the nuisance of ground vibration in urban environments, all motivate designs of defence structures to lessen the impact of seismic and ground vibration waves on buildings. Low frequency waves, in the range 1-10 Hz for earthquakes and up to a few tens of Hz for vibrations generated by human activities, cause a large amount of damage, or inconvenience; depending on the geological conditions they can travel considerable distances and may match the resonant fundamental frequency of buildings. The ultimate aim of any seismic metamaterial, or any other seismic shield, is to protect over this entire range of frequencies; the long wavelengths involved, and low frequency, have meant this has been unachievable to date. Notably this is scalable and the effects also hold for smaller devices in ultrasonics. There are three approaches to obtaining shielding effects: bragg scattering, locally resonant sub-wavelength inclusions and zero-frequency stop-band media. The former two have been explored, but the latter has not and is examined here. Elastic flexural waves, applicable in the mechanical vibrations of thin elastic plates, can be designed to have a broad zero-frequency stop-band using a periodic array of very small clamped circles. Inspired by this experimental and theoretical observation, all be it in a situation far removed from seismic waves, we demonstrate that it is possible to achieve elastic surface (Rayleigh) wave reflectors at very large wavelengths in structured soils modelled as a fully elastic layer periodically clamped to bedrock. We identify zero frequency stop-bands that only exist in the limit of columns of concrete clamped at their base to the bedrock. In a realistic configuration of a sedimentary basin 15 m deep we observe a zero frequency stop-band covering a broad frequency range of 0-30 Hz.

Ultrasound-guided versus computed tomography-scan guided biopsy of pleural-based lung lesions

PubMed Central

Khosla, Rahul; McLean, Anna W; Smith, Jessica A

2016-01-01

Background: Computed tomography (CT) guided biopsies have long been the standard technique to obtain tissue from the thoracic cavity and is traditionally performed by interventional radiologists. Ultrasound (US) guided biopsy of pleural-based lesions, performed by pulmonologists is gaining popularity and has the advantage of multi-planar imaging, real-time technique, and the absence of radiation exposure to patients. In this study, we aim to determine the diagnostic accuracy, the time to diagnosis after the initial consult placement, and the complications rates between the two different modalities. Methods: A retrospective study of electronic medical records was done of patients who underwent CT-guided biopsies and US-guided biopsies for pleural-based lesions between 2005 and 2014 and the data collected were analyzed for comparing the two groups. Results: A total of 158 patients underwent 162 procedures during the study period. 86 patients underwent 89 procedures in the US group, and 72 patients underwent 73 procedures in the CT group. The overall yield in the US group was 82/89 (92.1%) versus 67/73 (91.8%) in the CT group (P = 1.0). Average days to the procedure was 7.2 versus 17.5 (P = 0.00001) in the US and CT group, respectively. Complication rate was higher in CT group 17/73 (23.3%) versus 1/89 (1.1%) in the US group (P < 0.0001). Conclusions: For pleural-based lesions the diagnostic accuracy of US guided biopsy is similar to that of CT-guided biopsy, with a lower complication rate and a significantly reduced time to the procedure. PMID:27625440

Use of hydrogel breast biopsy tissue markers reduces the need for wire localization.

PubMed

Blumencranz, Peter W; Ellis, Debra; Barlowe, Kylee

2014-10-01

The purpose of this study was to determine whether breast biopsy tissue markers composed of an ultrasound-visible hydrogel reduced the need for preoperative wire localization (WL) in patients undergoing a partial mastectomy. A single-surgeon, single-institution, retrospective chart review was performed on 691 consecutive female patients, with mean age 67 years (range 36-98 years), from 2009 to 2012 undergoing partial mastectomies after percutaneous biopsies by stereotactic or ultrasound guidance. Overall, the use of WL was more frequent in patients who had standard (other) markers placed during biopsy as opposed to those with hydrogel markers (HydroMARK). For stereotactic biopsy, 75.8 % of patients with a standard marker required WL versus 17.1 % with HydroMARK and for ultrasound biopsy, 22.6 % standard versus 4.3 % HydroMARK (p < .0001, p < .0001). In some cases where hydrogel markers were used, WL was used for "bracketing" because of the presence of microcalcifications. In cases where standard markers were used, WL was not used because of either IOUS visibility of residual lesion or marker visibility. Specimen volume and re-excision rate were comparable between patients with hydrogel and standard markers, showing no significant differences (p = .1673, p = .1813 respectively). Hydrogel biopsy tissue markers optimize the surgeon's ability to perform a partial mastectomy without the use of WL. HydroMARK was as effective as a standard marker in terms of partial mastectomy specimen volume and re-excision rate. This yields potential for cost savings, increased efficacy in operating room and radiology scheduling, and patient comfort and convenience.

Multicentre evaluation of targeted and systematic biopsies using magnetic resonance and ultrasound image-fusion guided transperineal prostate biopsy in patients with a previous negative biopsy.

PubMed

Hansen, Nienke L; Kesch, Claudia; Barrett, Tristan; Koo, Brendan; Radtke, Jan P; Bonekamp, David; Schlemmer, Heinz-Peter; Warren, Anne Y; Wieczorek, Kathrin; Hohenfellner, Markus; Kastner, Christof; Hadaschik, Boris

2017-11-01

To evaluate the detection rates of targeted and systematic biopsies in magnetic resonance imaging (MRI) and ultrasound (US) image-fusion transperineal prostate biopsy for patients with previous benign transrectal biopsies in two high-volume centres. A two centre prospective outcome study of 487 patients with previous benign biopsies that underwent transperineal MRI/US fusion-guided targeted and systematic saturation biopsy from 2012 to 2015. Multiparametric MRI (mpMRI) was reported according to Prostate Imaging Reporting and Data System (PI-RADS) Version 1. Detection of Gleason score 7-10 prostate cancer on biopsy was the primary outcome. Positive (PPV) and negative (NPV) predictive values including 95% confidence intervals (95% CIs) were calculated. Detection rates of targeted and systematic biopsies were compared using McNemar's test. The median (interquartile range) PSA level was 9.0 (6.7-13.4) ng/mL. PI-RADS 3-5 mpMRI lesions were reported in 343 (70%) patients and Gleason score 7-10 prostate cancer was detected in 149 (31%). The PPV (95% CI) for detecting Gleason score 7-10 prostate cancer was 0.20 (±0.07) for PI-RADS 3, 0.32 (±0.09) for PI-RADS 4, and 0.70 (±0.08) for PI-RADS 5. The NPV (95% CI) of PI-RADS 1-2 was 0.92 (±0.04) for Gleason score 7-10 and 0.99 (±0.02) for Gleason score ≥4 + 3 cancer. Systematic biopsies alone found 125/138 (91%) Gleason score 7-10 cancers. In patients with suspicious lesions (PI-RADS 4-5) on mpMRI, systematic biopsies would not have detected 12/113 significant prostate cancers (11%), while targeted biopsies alone would have failed to diagnose 10/113 (9%). In equivocal lesions (PI-RADS 3), targeted biopsy alone would not have diagnosed 14/25 (56%) of Gleason score 7-10 cancers, whereas systematic biopsies alone would have missed 1/25 (4%). Combination with PSA density improved the area under the curve of PI-RADS from 0.822 to 0.846. In patients with high probability mpMRI lesions, the highest detection rates of Gleason

Design and evaluation of an ultra-slim objective for in-vivo deep optical biopsy

PubMed Central

Landau, Sara M.; Liang, Chen; Kester, Robert T.; Tkaczyk, Tomasz S.; Descour, Michael R.

2010-01-01

An estimated 1.6 million breast biopsies are performed in the US each year. In order to provide real-time, in-vivo imaging with sub-cellular resolution for optical biopsies, we have designed an ultra-slim objective to fit inside the 1-mm-diameter hypodermic needles currently used for breast biopsies to image tissue stained by the fluorescent probe proflavine. To ensure high-quality imaging performance, experimental tests were performed to characterize fiber bundle’s light-coupling efficiency and simulations were performed to evaluate the impact of candidate lens materials’ autofluorescence. A prototype of NA = 0.4, 250-µm field of view, ultra-slim objective optics was built and tested, yielding diffraction-limited performance and estimated resolution of 0.9 µm. When used in conjunction with a commercial coherent fiber bundle to relay the image formed by the objective, the measured resolution was 2.5 µm. PMID:20389489

Small Molecules for Early Endosome-Specific Patch Clamping.

PubMed

Chen, Cheng-Chang; Butz, Elisabeth S; Chao, Yu-Kai; Grishchuk, Yulia; Becker, Lars; Heller, Stefan; Slaugenhaupt, Susan A; Biel, Martin; Wahl-Schott, Christian; Grimm, Christian

2017-07-20

To resolve the subcellular distribution of endolysosomal ion channels, we have established a novel experimental approach to selectively patch clamp Rab5 positive early endosomes (EE) versus Rab7/LAMP1-positive late endosomes/lysosomes (LE/LY). To functionally characterize ion channels in endolysosomal membranes with the patch-clamp technique, it is important to develop techniques to selectively enlarge the respective organelles. We found here that two small molecules, wortmannin and latrunculin B, enlarge Rab5-positive EE when combined but not Rab7-, LAMP1-, or Rab11 (RE)-positive vesicles. The two compounds act rapidly, specifically, and are readily applicable in contrast to genetic approaches or previously used compounds such as vacuolin, which enlarges EE, RE, and LE/LY. We apply this approach here to measure currents mediated by TRPML channels, in particular TRPML3, which we found to be functionally active in both EE and LE/LY in overexpressing cells as well as in endogenously expressing CD11b+ lung-tissue macrophages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Liver biopsy under hypnosis.

PubMed

Adams, P C; Stenn, P G

1992-09-01

Two patients underwent outpatient percutaneous liver biopsy under hypnosis without complications. One patient had severe anxiety about the procedure because of a previous adverse experience with liver biopsy and the other had a history of severe allergy to local anesthesia. Both patients had undergone a session of hypnosis at least once prior to the biopsy. One received no local anesthetic and the other received 1% lidocaine as a local anesthetic. Both patients were completely cooperative during the procedure with the required respiratory maneuvers. Both patients stated that they were aware of the procedure under hypnosis but described no pain and would be most willing to have the procedure done under hypnosis in the future. Hypnosis can be a useful method of preparing carefully selected patients for percutaneous liver biopsy.

Clamp-crushing vs. radiofrequency-assisted liver resection:changes in liver function tests.

PubMed

Palibrk, Ivan; Milicic, Biljana; Stojiljkovic, Ljuba; Manojlovic, Nebojsa; Dugalic, Vladimir; Bumbasirevic, Vesna; Kalezic, Nevena; Zuvela, Marinko; Milicevic, Miroslav

2012-05-01

Liver resection is the gold standard in managing patients with metastatic or primary liver cancer. The aim of our study was to compare the traditional clamp-crushing technique to the radiofrequency- assisted liver resection technique in terms of postoperative liver function. Liver function was evaluated preoperatively and on postoperative days 3 and 7. Liver synthetic function parameters (serum albumin level, prothrombin time and international normalized ratio), markers of hepatic injury and necrosis (serum alanine aminotransferase, aspartate aminotransferase and total bilirubin level) and microsomal activity (quantitative lidocaine test) were compared. Forty three patients completed the study (14 had clamp-crushing and 29 had radiofrequency assisted liver resection). The groups did not differ in demographic characteristics, pre-operative liver function, operative time and perioperative transfusion rate. In postoperative period, there were similar changes in monitored parameters in both groups except albumin levels, that were higher in radiofrequency-assisted liver resection group (p=0.047). Both, traditional clamp-crushing technique and radiofrequency assisted liver resection technique, result in similar postoperative changes of most monitored liver function parameters.

Can robots patch-clamp as well as humans? Characterization of a novel sodium channel mutation

PubMed Central

Estacion, M; Choi, J S; Eastman, E M; Lin, Z; Li, Y; Tyrrell, L; Yang, Y; Dib-Hajj, S D; Waxman, S G

2010-01-01

Ion channel missense mutations cause disorders of excitability by changing channel biophysical properties. As an increasing number of new naturally occurring mutations have been identified, and the number of other mutations produced by molecular approaches such as in situ mutagenesis has increased, the need for functional analysis by patch-clamp has become rate limiting. Here we compare a patch-clamp robot using planar-chip technology with human patch-clamp in a functional assessment of a previously undescribed Nav1.7 sodium channel mutation, S211P, which causes erythromelalgia. This robotic patch-clamp device can increase throughput (the number of cells analysed per day) by 3- to 10-fold. Both modes of analysis show that the mutation hyperpolarizes activation voltage dependence (−8 mV by manual profiling, −11 mV by robotic profiling), alters steady-state fast inactivation so that it requires an additional Boltzmann function for a second fraction of total current (∼20% manual, ∼40% robotic), and enhances slow inactivation (hyperpolarizing shift −15 mV by human, −13 mV robotic). Manual patch-clamping demonstrated slower deactivation and enhanced (∼2-fold) ramp response for the mutant channel while robotic recording did not, possibly due to increased temperature and reduced signal-to-noise ratio on the robotic platform. If robotic profiling is used to screen ion channel mutations, we recommend that each measurement or protocol be validated by initial comparison to manual recording. With this caveat, we suggest that, if results are interpreted cautiously, robotic patch-clamp can be used with supervision and subsequent confirmation from human physiologists to facilitate the initial profiling of a variety of electrophysiological parameters of ion channel mutations. PMID:20123784

Optimizing RNA Extraction of Renal Papilla Biopsy Tissue in Kidney Stone Formers: A New Methodology for Genomic Study.

PubMed

Taguchi, Kazumi; Usawachintachit, Manint; Hamamoto, Shuzo; Unno, Rei; Tzou, David T; Sherer, Benjamin A; Wang, Yongmei; Okada, Atsushi; Stoller, Marshall L; Yasui, Takahiro; Chi, Thomas

2017-09-01

Endoscopic tools have provided versatile examination and treatment for kidney stone procedures. Despite endourologists researching urinary stone disease using endoscopes to collect tissue, this tissue collection method is limited. Endoscopically removed tissues are small in size, restricting the types of genome-based examination possible. We investigated a new method of renal papilla biopsy and RNA extraction to establish a genomic research methodology for kidney stone disease. We conducted a prospective multi-institutional study and collected renal papilla specimens from consecutive percutaneous nephrolithotomy and ureteroscopy (URS) cases performed for removal of upper urinary tract stones. Renal papilla tissue was extracted using ureteroscopic biopsy forceps after stone removal. RNA was extracted using two different extraction kits, and their quantity and quality were examined. Additionally, the impact of biopsy on surgical complications was compared between cases performed with and without biopsy by matched case-control analysis adjusted for age, gender, body mass index, bilaterality, and stone burden. A total of 90 biopsies from 49 patients were performed, and the median duration between specimen collection and RNA extraction was 61 days. Both univariate and multivariate analyses showed BIGopsy ® forceps usage significantly increased the total yield (p = 0.004) and quality (p = 0.001 for A260/280, p = 0.004 for A260/A230) of extracted RNA. Extraction using the RNeasy Micro Kit ® also improved A260/A230, whereas reduced RNA integrity number of extracted RNA by univariate and multivariate analyses (p = 0.002 and p < 0.001, respectively). Moreover, matched case-control study demonstrated that endoscopic renal papilla biopsy caused no significant surgical complications, including bleeding, decreased stone clearance and hematocrit, and renal dysfunction. Biopsies during URS imparted an average of 20 minutes of procedure time over nonbiopsy

Temporal artery biopsy size does not matter.

PubMed

Kaptanis, Sarantos; Perera, Joanne K; Halkias, Constantine; Caton, Nadine; Alarcon, Lida; Vig, Stella

2014-12-01

This study aimed to clarify whether positive temporal artery biopsies had a greater sample length than negative biopsies in temporal arteritis. It has been suggested that biopsy length should be at least 1 cm to improve diagnostic accuracy. A retrospective review of 149 patients who had 151 temporal artery biopsies was conducted. Twenty biopsies were positive (13.3%), 124 negative (82.1%) and seven samples were insufficient (4.6%). There was no clinically significant difference in the mean biopsy size between positive (0.7 cm) and negative samples (0.65 cm) (t-test: p = .43 NS). Ninety-four patients fulfilled all three ACR criteria prior to biopsy (62.3%) and four patients (2.6%) changed ACR score from 2 to 3 after biopsy. Treatment should not be delayed in anticipation of the biopsy or withheld in the case of a negative biopsy if the patient's symptoms improve. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Inertial piezoelectric linear motor driven by a single-phase harmonic wave with automatic clamping mechanism

NASA Astrophysics Data System (ADS)

He, Liangguo; Chu, Yuheng; Hao, Sai; Zhao, Xiaoyong; Dong, Yuge; Wang, Yong

2018-05-01

A novel, single-phase, harmonic-driven, inertial piezoelectric linear motor using an automatic clamping mechanism was designed, fabricated, and tested to reduce the sliding friction and simplify the drive mechanism and power supply control of the inertial motor. A piezoelectric bimorph and a flexible hinge were connected in series to form the automatic clamping mechanism. The automatic clamping mechanism was used as the driving and clamping elements. A dynamic simulation by Simulink was performed to prove the feasibility of the motor. The finite element method software COMSOL was used to design the structure of the motor. An experimental setup was built to validate the working principle and evaluate the performance of the motor. The prototype motor outputted a no-load velocity of 3.178 mm/s at a voltage of 220 Vp-p and a maximum traction force of 4.25 N under a preload force of 8 N. The minimum resolution of 1.14 μm was achieved at a driving frequency of 74 Hz, a driving voltage of 50 Vp-p, and a preload force of 0 N.

Prospective evaluation of magnetic resonance imaging guided in-bore prostate biopsy versus systematic transrectal ultrasound guided prostate biopsy in biopsy naïve men with elevated prostate specific antigen.

PubMed

Quentin, Michael; Blondin, Dirk; Arsov, Christian; Schimmöller, Lars; Hiester, Andreas; Godehardt, Erhard; Albers, Peter; Antoch, Gerald; Rabenalt, Robert

2014-11-01

Magnetic resonance imaging guided biopsy is increasingly performed to diagnose prostate cancer. However, there is a lack of well controlled, prospective trials to support this treatment method. We prospectively compared magnetic resonance imaging guided in-bore biopsy with standard systematic transrectal ultrasound guided biopsy in biopsy naïve men with increased prostate specific antigen. We performed a prospective study in 132 biopsy naïve men with increased prostate specific antigen (greater than 4 ng/ml). After 3 Tesla functional multiparametric magnetic resonance imaging patients were referred for magnetic resonance imaging guided in-bore biopsy of prostate lesions (maximum 3) followed by standard systematic transrectal ultrasound guided biopsy (12 cores). We analyzed the detection rates of prostate cancer and significant prostate cancer (greater than 5 mm total cancer length or any Gleason pattern greater than 3). A total of 128 patients with a mean ± SD age of 66.1 ± 8.1 years met all study requirements. Median prostate specific antigen was 6.7 ng/ml (IQR 5.1-9.0). Transrectal ultrasound and magnetic resonance imaging guided biopsies provided the same 53.1% detection rate, including 79.4% and 85.3%, respectively, for significant prostate cancer. Magnetic resonance imaging and transrectal ultrasound guided biopsies missed 7.8% and 9.4% of clinically significant prostate cancers, respectively. Magnetic resonance imaging biopsy required significantly fewer cores and revealed a higher percent of cancer involvement per biopsy core (each p <0.01). Combining the 2 methods provided a 60.9% detection rate with an 82.1% rate for significant prostate cancer. Magnetic resonance imaging guided in-bore and systematic transrectal ultrasound guided biopsies achieved equally high detection rates in biopsy naïve patients with increased prostate specific antigen. Magnetic resonance imaging guided in-bore biopsies required significantly fewer cores and revealed a

Liquid biopsy for brain tumors.

PubMed

Shankar, Ganesh M; Balaj, Leonora; Stott, Shannon L; Nahed, Brian; Carter, Bob S

2017-10-01

Minimally invasive methods will augment the clinical approach for establishing the diagnosis or monitoring treatment response of central nervous system tumors. Liquid biopsy by blood or cerebrospinal fluid sampling holds promise in this regard. Areas covered: In this literature review, the authors highlight recent studies describing the analysis of circulating tumor cells, cell free nucleic acids, and extracellular vesicles as strategies to accomplish liquid biopsy in glioblastoma and metastatic tumors. The authors then discuss the continued efforts to improve signal detection, standardize the liquid biopsy handling and preparation, develop platforms for clinical application, and establish a role for liquid biopsies in personalized medicine. Expert commentary: As the technologies used to analyze these biomarkers continue to evolve, we propose that there is a future potential to precisely diagnose and monitor treatment response with liquid biopsies.

Safety of minimally invasive mitral valve surgery without aortic cross-clamp.

PubMed

Umakanthan, Ramanan; Leacche, Marzia; Petracek, Michael R; Kumar, Sathappan; Solenkova, Nataliya V; Kaiser, Clayton A; Greelish, James P; Balaguer, Jorge M; Ahmad, Rashid M; Ball, Stephen K; Hoff, Steven J; Absi, Tarek S; Kim, Betty S; Byrne, John G

2008-05-01

We developed a technique for open heart surgery through a small (5 cm) right-anterolateral thoracotomy without aortic cross-clamp. One hundred and ninety-five consecutive patients (103 male and 92 female), age 69 +/- 8 years, underwent surgery between January 2006 and July 2007. Mean preoperative New York Heart Association function class was 2.2 +/- 0.7. Thirty-five patients (18%) had an ejection fraction 0.35 or less. Cardiopulmonary bypass was instituted through femoral (176 of 195, 90%), axillary (18 of 195, 9%), or direct aortic (1 of 195, 0.5%) cannulation. Under cold fibrillatory arrest (mean temperature 28.2 degrees C) without aortic cross-clamp, mitral valve repair (72 of 195, 37%), mitral valve replacement (117 of 195, 60%), or other (6 of 195, 3%) procedures were performed. Concomitant procedures included maze (45 of 195, 23%), patent foramen ovale closure (42 of 195, 22%) and tricuspid valve repair (16 of 195, 8%), or replacement (4 of 195, 2%). Thirty-day mortality was 3% (6 of 195). Duration of fibrillatory arrest, cardiopulmonary bypass, and "skin to skin" surgery were 88 +/- 32, 118 +/- 52, and 280 +/- 78 minutes, respectively. Ten patients (5%) underwent reexploration for bleeding and 44% did not receive any blood transfusions. Six patients (3%) sustained a postoperative stroke, eight (4%) developed low cardiac output syndrome, and two (1%) developed renal failure requiring hemodialysis. Mean length of hospital stay was 7 +/- 4.8 days. This simplified technique of minimally invasive open heart surgery is safe and easily reproducible. Fibrillatory arrest without aortic cross-clamping, with coronary perfusion against an intact aortic valve, does not increase the risk of stroke or low cardiac output. It may be particularly useful in higher risk patients in whom sternotomy with aortic clamping is less desirable.

Image guided biopsy of the pleura: a useful diagnostic tool even when fluid is minimal

PubMed Central

Manu, Mohan K; Prakashini, Koteshwara; Mohapatra, Aswini Kumar; Kudva, Ranjini

2014-01-01

A man in his late thirties presented with left-sided chest pain, recurrent fever and cough. Radiographical study revealed left pleural effusion which on ultrasonic imaging was minimal and non-tappable. Image guided trucut pleural biopsy yielded pleural specimens which helped in confirming the diagnosis of tuberculosis. PMID:24980995

Prospective, Randomized, Pathologist-Blinded Study of Disposable Alligator-Jaw Biopsy Forceps for Gastric Mucosal Biopsy

PubMed Central

Abudayyeh, Suhaib; Hoffman, Jill; El-Zimaity, Hala T.; Graham, David Y.

2010-01-01

Background Endoscopic biopsy forceps differ in the size and shape of the biopsy cup and the presence or absence of a needle. Methods We compared 4 different “large cup” forceps (3 with needles designed for 2.8 mm biopsy channels. A gastric antral and corpus biopsy were obtained with each. Parameters examined included: weight (mg), length (mm), orientation (poor, good), intactness (1, 2, or 3 pieces), depth (superficial, above muscularis mucosae, included muscularis mucosae), crush artifact (yes, no), and overall adequacy (inadequate, suboptimal, adequate). Results 24 patients were enrolled (191 biopsies). The median length was approximately 5 mm (range 1.1 to 8.2 mm). Histologically inadequate specimens were present in 4% with the forceps without needle compared to 16% of those with needles (P = 0.061) and there were significantly fewer specimens in 3 or more pieces than did the forceps with needles 2.1% vs. 12..6% (P<0.05). Conclusions Current alligator style forceps provide a high proportion of acceptable specimens with only minor differences between brands. Forceps from one source were least preferred by endoscopy assistants and had the highest rates of inadequate biopsies and biopsies with crush artifact. Forceps without needles provide histologically acceptable samples slightly more frequently than those with needles. PMID:18799373

Prospective, randomized, pathologist-blinded study of disposable alligator-jaw biopsy forceps for gastric mucosal biopsy.

PubMed

Abudayyeh, S; Hoffman, J; El-Zimaity, H T; Graham, D Y

2009-05-01

Endoscopic biopsy forceps differ in the size and shape of the biopsy cup and the presence or absence of a needle. We compared four different "large cup" forceps (three with needles) designed for 2.8mm biopsy channels. A gastric antral and corpus biopsy were obtained with each. Parameters examined included: weight (mg), length (mm), orientation (poor, good), intactness (1, 2, or 3 pieces), depth (superficial, above muscularis mucosae, included muscularis mucosae), crush artefact (yes, no), and overall adequacy (inadequate, suboptimal, adequate). Twenty-four patients were enrolled (191 biopsies). The median length was approximately 5mm (range 1.1-8.2mm). Histologically inadequate specimens were present in 4% with the forceps without needle compared to 16% of those with needles (P=0.061) and there were significantly fewer specimens in three or more pieces than did the forceps with needles 2.1% vs. 12.6% (P<0.05). Current alligator style forceps provide a high proportion of acceptable specimens with only minor differences between brands. Forceps from one source were least preferred by endoscopy assistants and had the highest rates of inadequate biopsies and biopsies with crush artefact. Forceps without needles provide histologically acceptable samples slightly more frequently than those with needles.

Perforated Patch-clamp Recording of Mouse Olfactory Sensory Neurons in Intact Neuroepithelium: Functional Analysis of Neurons Expressing an Identified Odorant Receptor

PubMed Central

Jarriault, David; Grosmaitre, Xavier

2015-01-01

Analyzing the physiological responses of olfactory sensory neurons (OSN) when stimulated with specific ligands is critical to understand the basis of olfactory-driven behaviors and their modulation. These coding properties depend heavily on the initial interaction between odor molecules and the olfactory receptor (OR) expressed in the OSNs. The identity, specificity and ligand spectrum of the expressed OR are critical. The probability to find the ligand of the OR expressed in an OSN chosen randomly within the epithelium is very low. To address this challenge, this protocol uses genetically tagged mice expressing the fluorescent protein GFP under the control of the promoter of defined ORs. OSNs are located in a tight and organized epithelium lining the nasal cavity, with neighboring cells influencing their maturation and function. Here we describe a method to isolate an intact olfactory epithelium and record through patch-clamp recordings the properties of OSNs expressing defined odorant receptors. The protocol allows one to characterize OSN membrane properties while keeping the influence of the neighboring tissue. Analysis of patch-clamp results yields a precise quantification of ligand/OR interactions, transduction pathways and pharmacology, OSNs' coding properties and their modulation at the membrane level.  PMID:26275097

Which aortic clamp strategy is better to reduce postoperative stroke and death

PubMed Central

Chen, Liyu; Hua, Xiumeng; Song, Jiangping; Wang, Liqing

2018-01-01

Abstract Background: Stroke is severe complication of coronary artery bypass grafting (CABG) which may be associated with clamp strategy, there are 2 strategies to clamp aorta including single aortic clamp (SAC) and partial aortic clamp (PAC). It is controversial that which clamping strategy is better to reduce the postoperative stroke and death, so this study aims to investigate which is better for reducing postoperative stroke and death within 30 days. Methods: We collected 469 patients who had on-pump CABG in Fuwai Hospital during January 2014 to July 2015. The SAC group consisted of 265 patients while the PAC group included 204 patients. We compared the 2 group patient difference. At the same time, 12 studies were identified by systematic search. The odds ratio (OR) was used as effect index to compare SAC and PAC strategy by fix-effect modeling. We also tested heterogeneity and publication bias. The primary end point of study was occurrence of postoperative stroke within 30 days of operation, the second end point of study was the incidence of 30-day mortality. Results: The single center retrospective study showed that the patients in the SAC group were older than those in the PAC group (62.5 ± 8.1 vs 60.3 ± 8.0 years, P = .01). The proportions of peripheral vascular disease and hypertension of SAC were higher than PAC (71 (26.8%) versus 36 (17.6%), P = .02; 183 (69.1%) versus 115 (56.4%), P = .01, respectively). Besides, the number of vascular anastomosis was more in the SAC group (3.29 ± 0.74 versus 2.97 ± 0.974, P < .001). The linear-regression analysis suggested that the time of cardiopulmonary bypass of SAC was shorter than the PAC group (93.2 ± 22.4 vs.103.4 ± 26.8 minutes, P-regression < .001) and postoperative death within 30-days was similar (1 (0.4%) vs. 2 (1.0%), P-regression = .47). There was no stroke occurring in both the groups. And the meta-analysis suggested the postoperative stroke and

Enhanced strain effect of aged acceptor-doped BaTiO3 ceramics with clamping domain structures

NASA Astrophysics Data System (ADS)

Wang, Lei; Zhou, Zhiyong; Zhao, Xiaobo; Liu, Zhen; Liang, Ruihong; Dong, Xianlin

2017-03-01

A clamping domain structure is proposed to improve the amount of non-180° domain switching in BaTiO3 based piezoelectric ceramics. Experimental results show a large unipolar strain of 0.23% at 5 kV/mm in aged 0.5 mol. % Mn doped BaTiO3 ceramics with clamping domain structures, and the normalized strain (d33*= Smax/Emax) reaches 600 pm/V at low electric fields of 2 or 3 kV/mm. In contrast, pure BaTiO3 ceramics with clamping domain structures exhibit no clear polarization constriction or strain enhancement at 3 kV/mm. Electron paramagnetic resonance spectra verify the existence of titanium vacancies, Mn2+ and Mn4+, in 0.5 mol. % Mn doped BaTiO3 ceramics. These results indicate that the enhanced strain effect can be attributed to the combined effect of the clamping domain structure and stabilization of defect dipoles. This method provides a general way to obtain large strain in ferroelectrics.

MRI/US fusion-guided prostate biopsy allows for equivalent cancer detection with significantly fewer needle cores in biopsy-naive men

PubMed Central

Yarlagadda, Vidhush K.; Lai, Win Shun; Gordetsky, Jennifer B.; Porter, Kristin K.; Nix, Jeffrey W.; Thomas, John V.; Rais-Bahrami, Soroush

2018-01-01

PURPOSE We aimed to investigate the efficiency and cancer detection of magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided prostate biopsy in a cohort of biopsy-naive men compared with standard-of-care systematic extended sextant transrectal ultrasonography (TRUS)-guided biopsy. METHODS From 2014 to 2016, 72 biopsy-naive men referred for initial prostate cancer evaluation who underwent MRI of the prostate were prospectively evaluated. Retrospective review was performed on 69 patients with lesions suspicious for malignancy who underwent MRI/US fusion-guided biopsy in addition to systematic extended sextant biopsy. Biometric, imaging, and pathology data from both the MRI-targeted biopsies and systematic biopsies were analyzed and compared. RESULTS There were no significant differences in overall prostate cancer detection when comparing MRI-targeted biopsies to standard systematic biopsies (P = 0.39). Furthermore, there were no significant differences in the distribution of severity of cancers based on grade groups in cases with cancer detection (P = 0.68). However, significantly fewer needle cores were taken during the MRI/US fusion-guided biopsy compared with systematic biopsy (63% less cores sampled, P < 0.001) CONCLUSION In biopsy-naive men, MRI/US fusion-guided prostate biopsy offers equal prostate cancer detection compared with systematic TRUS-guided biopsy with significantly fewer tissue cores using the targeted technique. This approach can potentially reduce morbidity in the future if used instead of systematic biopsy without sacrificing the ability to detect prostate cancer, particularly in cases with higher grade disease. PMID:29770762

Automated Patch-Clamp Methods for the hERG Cardiac Potassium Channel.

PubMed

Houtmann, Sylvie; Schombert, Brigitte; Sanson, Camille; Partiseti, Michel; Bohme, G Andrees

2017-01-01

The human Ether-a-go-go Related Gene (hERG) product has been identified as a central ion channel underlying both familial forms of elongated QT interval on the electrocardiogram and drug-induced elongation of the same QT segment. Indeed, reduced function of this potassium channel involved in the repolarization of the cardiac action potential can produce a type of life-threatening cardiac ventricular arrhythmias called Torsades de Pointes (TdP). Therefore, hERG inhibitory activity of newly synthetized molecules is a relevant structure-activity metric for compound prioritization and optimization in medicinal chemistry phases of drug discovery. Electrophysiology remains the gold standard for the functional assessment of ion channel pharmacology. The recent years have witnessed automatization and parallelization of the manual patch-clamp technique, allowing higher throughput screening on recombinant hERG channels. However, the multi-well plate format of automatized patch-clamp does not allow visual detection of potential micro-precipitation of poorly soluble compounds. In this chapter we describe bench procedures for the culture and preparation of hERG-expressing CHO cells for recording on an automated patch-clamp workstation. We also show that the sensitivity of the assay can be improved by adding a surfactant to the extracellular medium.

Automated patch clamp on mESC-derived cardiomyocytes for cardiotoxicity prediction.

PubMed

Stoelzle, Sonja; Haythornthwaite, Alison; Kettenhofen, Ralf; Kolossov, Eugen; Bohlen, Heribert; George, Michael; Brüggemann, Andrea; Fertig, Niels

2011-09-01

Cardiovascular side effects are critical in drug development and have frequently led to late-stage project terminations or even drug withdrawal from the market. Physiologically relevant and predictive assays for cardiotoxicity are hence strongly demanded by the pharmaceutical industry. To identify a potential impact of test compounds on ventricular repolarization, typically a variety of ion channels in diverse heterologously expressing cells have to be investigated. Similar to primary cells, in vitro-generated stem cell-derived cardiomyocytes simultaneously express cardiac ion channels. Thus, they more accurately represent the native situation compared with cell lines overexpressing only a single type of ion channel. The aim of this study was to determine if stem cell-derived cardiomyocytes are suited for use in an automated patch clamp system. The authors show recordings of cardiac ion currents as well as action potential recordings in readily available stem cell-derived cardiomyocytes. Besides monitoring inhibitory effects of reference compounds on typical cardiac ion currents, the authors revealed for the first time drug-induced modulation of cardiac action potentials in an automated patch clamp system. The combination of an in vitro cardiac cell model with higher throughput patch clamp screening technology allows for a cost-effective cardiotoxicity prediction in a physiologically relevant cell system.

Yield of diagnostic procedures for invasive fungal infections in neutropenic febrile patients with chest computed tomography abnormalities.

PubMed

Ho, Dora Y; Lin, Margaret; Schaenman, Joanna; Rosso, Fernando; Leung, Ann N C; Coutre, Steven E; Sista, Ramachandra R; Montoya, Jose G

2011-01-01

Haematological patients with neutropenic fever are frequently evaluated with chest computed tomography (CT) to rule out invasive fungal infections (IFI). We retrospectively analysed data from 100 consecutive patients with neutropenic fever and abnormal chest CT from 1998 to 2005 to evaluate their chest CT findings and the yield of diagnostic approaches employed. For their initial CTs, 79% had nodular opacities, with 24.1% associated with the halo sign. Other common CT abnormalities included pleural effusions (48%), ground glass opacities (37%) and consolidation (31%). The CT findings led to a change in antifungal therapy in 54% of the patients. Fifty-six patients received diagnostic procedures, including 46 bronchoscopies, 25 lung biopsies and seven sinus biopsies, with a diagnostic yield for IFI of 12.8%, 35.0% and 83.3%, respectively. In conclusion, chest CT plays an important role in the evaluation of haematological patients with febrile neutropenia and often leads to a change in antimicrobial therapy. Pulmonary nodules are the most common radiological abnormality. Sinus or lung biopsies have a high-diagnostic yield for IFI as compared to bronchoscopy. Patients with IFI may not have sinus/chest symptoms, and thus, clinicians should have a low threshold for performing sinus/chest imaging, and if indicated and safe, a biopsy of the abnormal areas. © 2009 Blackwell Verlag GmbH.

Liquid biopsy for brain tumors

PubMed Central

Shankar, Ganesh M.; Balaj, Leonora; Stott, Shannon L.; Nahed, Brian; Carter, Bob S.

2018-01-01

Introduction Minimally invasive methods will augment the clinical approach for establishing the diagnosis or monitoring treatment response of central nervous system tumors. Liquid biopsy by blood or cerebrospinal fluid sampling holds promise in this regard. Areas covered In this literature review, the authors highlight recent studies describing the analysis of circulating tumor cells, cell free nucleic acids, and extracellular vesicles as strategies to accomplish liquid biopsy in glioblastoma and metastatic tumors. The authors then discuss the continued efforts to improve signal detection, standardize the liquid biopsy handling and preparation, develop platforms for clinical application, and establish a role for liquid biopsies in personalized medicine. Expert commentary As the technologies used to analyze these biomarkers continue to evolve, we propose that there is a future potential to precisely diagnose and monitor treatment response with liquid biopsies. PMID:28875730

Comparison of Keyes Punch Biopsy Instrument with Cervical Punch Biopsy Forceps for Diagnosing Cervical Lesions.

PubMed

Tyagi, Natasha; Suneja, Amita; Mishra, Kiran; Jain, Sandhya; Vaid, Neelam Bala; Guleria, Kiran

2017-01-01

To assess the feasibility and efficacy of Keyes punch biopsy instrument (KP) in diagnosing cervical lesions and compare it with cervical punch biopsy forceps (CP). 75 women having satisfactory colposcopy with abnormal transformation zone were included and paired colposcopic directed biopsies were taken using KP followed by CP from the same target area. It was feasible in all cases to take cervical biopsy with KP after increasing its effective length. The volume of gross specimen obtained by KP was less than CP (0.076 ± 0.097 vs. 0.101 ± 0.156 cm3, p = 0.061), however on microscopic examination, mean length and mean depth of tissue in KP was greater than CP by 0.06 mm (p = 0.810) and 0.14 mm (p = 0.634) respectively. Exact agreement was found with the final surgical specimen in 42% of cases in both the biopsy forceps. KP is almost at par with CP for diagnosing preinvasive cervical lesions and is a useful adjunct to the existing armamentarium of biopsy forceps. © 2016 S. Karger AG, Basel.

A-Mating-Type Gene Expression Can Drive Clamp Formation in the Bipolar Mushroom Pholiota microspora (Pholiota nameko) ▿

PubMed Central

Yi, Ruirong; Mukaiyama, Hiroyuki; Tachikawa, Takashi; Shimomura, Norihiro; Aimi, Tadanori

2010-01-01

In the bipolar basidiomycete Pholiota microspora, a pair of homeodomain protein genes located at the A-mating-type locus regulates mating compatibility. In the present study, we used a DNA-mediated transformation system in P. microspora to investigate the homeodomain proteins that control the clamp formation. When a single homeodomain protein gene (A3-hox1 or A3-hox2) from the A3 monokaryon strain was transformed into the A4 monokaryon strain, the transformants produced many pseudoclamps but very few clamps. When two homeodomain protein genes (A3-hox1 and A3-hox2) were transformed either separately or together into the A4 monokaryon, the ratio of clamps to the clamplike cells in the transformants was significantly increased to ca. 50%. We therefore concluded that the gene dosage of homeodomain protein genes is important for clamp formation. When the sip promoter was connected to the coding region of A3-hox1 and A3-hox2 and the fused fragments were introduced into NGW19-6 (A4), the transformants achieved more than 85% clamp formation and exhibited two nuclei per cell, similar to the dikaryon (NGW12-163 × NGW19-6). The results of real-time reverse transcription-PCR confirmed that sip promoter activity is greater than that of the native promoter of homeodomain protein genes in P. microspora. Thus, we concluded that nearly 100% clamp formation requires high expression levels of homeodomain protein genes and that altered expression of the A-mating-type genes alone is sufficient to drive true clamp formation. PMID:20453073

A pilot study of EUS-guided through-the-needle forceps biopsy (with video).

PubMed

Nakai, Yousuke; Isayama, Hiroyuki; Chang, Kenneth J; Yamamoto, Natsuyo; Mizuno, Suguru; Mohri, Dai; Kogure, Hirofumi; Matsubara, Saburo; Tada, Minoru; Koike, Kazuhiko

2016-07-01

In EUS-guided FNA (EUS-FNA), small-caliber needles are preferable for optimal cytologic yield, whereas large ones are preferable when histologic specimens are needed. Because of the rigidity and friction induced by its large caliber, however, technical limitation does exist in a 19-gauge FNA needle. Recent development of miniature biopsy forceps enables EUS-guided through-the-needle forceps biopsy (EUS-TTNFB). The aim of this study is to evaluate safety and efficacy of EUS-TTNFB. Eighteen sessions of EUS-TTNFB in 17 patients with solid lesions were performed by using a 0.75-mm biopsy forceps through a 19-gauge FNA needle. Technical feasibility, safety, and diagnostic yield of EUS-TTNFB were retrospectively studied. A total of 49 passes, a median of 3 passes per session, were performed, and the needle puncture, advancement and removal of the biopsy forceps, and subsequent EUS-FNA were technically successful in all patients. No adverse events were observed other than one case with hyperamylasemia without pancreatitis. Macroscopic histologic core by EUS-TTNFB was obtained at a rate of 71% per pass. The tissue acquisition rate by EUS-TTNFB alone was 67% per pass and 100% per session. When EUS-TTNFB and subsequent EUS-FNA were combined, the tissue acquisition rate was 94% per pass. The accuracy of combined EUS-TTNFB and EUS-FNA to diagnose malignancy was 88% per pass and 94% per session. With a single pass of EUS-TTNFB and EUS-FNA, the tissue acquisition rate was 89%, and the accuracy to diagnose malignancy was 83%. EUS-TTNFB was safe and technically feasible and provided additional tissue acquisition with a single puncture of a 19-gauge FNA needle. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

A CT-guided fat transversing coaxial biopsy technique for pancreatic lesion biopsy that avoids major organs and vessels

PubMed Central

Lin, Chia-Ying; Ou, Ming-Ching; Liu, Yi-Sheng; Chuang, Ming-Tsung; Shan, Yan-Shen; Tsai, Hong-Ming; Wang, Chien-Kuo; Tsai, Yi-Shan

2017-01-01

Background/Aims: The purpose of this study is to report our results using a computed tomography (CT)-guided fat transversing coaxial biopsy technique for pancreatic lesion biopsy that avoids major organs and vessels. We retrospectively reviewed the records of patients referred to our department for pancreatic mass biopsy. Patients and Methods: The records of patients (from June 2008 to August 2014) in whom biopsy was performed under CT guidance with a coaxial needle using a fat transversing technique were reviewed. Patient demographic data and biopsy outcomes were collected. We aimed to compare differences between lesion size and biopsy outcome, the independent two-samples t-test was used. Results: A total of 122 patients who underwent 17-G coaxial needle biopsy were included. The mean pancreatic lesion size was 3.2 cm, and in 30 patients it was more than 4 cm. The majority of lesions were located in the head of the pancreas (44.3%). No transorgan biopsies were performed. In most patients, the biopsy was performed via a fat traversing detour route (93.4%), and a successful diagnosis was made based on the biopsy outcome in 96.7% patients. Complications occurred in five patients (4.1%); three of the patients developed a fever, and two developed pancreatitis. All patients recovered with symptomatic treatment. Conclusion: CT-guided coaxial core biopsy of pancreatic lesions using a fat detour route appears to be a safe and effective method for obtaining pancreatic lesion biopsies with a high success rate and low complication rate. PMID:29205187

21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Neurosurgical head holder (skull clamp). 882.4460 Section 882.4460 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4460 Neurosurgical head...

Use of a frameless computed tomography-guided stereotactic biopsy system for nasal biopsy in five dogs.

PubMed

Kuhlman, Gregory M; Taylor, Amanda R; Thieman-Mankin, Kelley M; Griffin, Jay; Cook, Audrey K; Levine, Jonathan M

2016-04-15

5 dogs (median age, 9 years; median body weight, 31 kg [68.2 lb]) with undefined nasal masses were examined after undergoing CT of the head and nasal biopsy via a rostral rhinoscopic or unaided (blind) approach because histologic results for collected biopsy specimens (inflammatory, necrotic, or hemorrhagic disease) suggested the specimens were nonrepresentative of the underlying disease process identified via CT (aggressive or malignant disease). Clinical signs at the time dogs were evaluated included open-mouth breathing, sneezing, or unilateral epistaxis. Histologic findings pertaining to the original biopsy specimens were suggestive of benign processes such as inflammation. In an attempt to obtain better representative specimens, a frameless CT-guided stereotactic biopsy system (CTSBS) was used to collect additional biopsy specimens from masses within the nasal and sinus passages of the dogs. The second set of biopsy specimens was histologically evaluated. Histologic evaluation of biopsy specimens collected via the CTSBS revealed results suggestive of malignant neoplasia (specifically, chondrosarcoma, hemangiopericytoma, or undifferentiated sarcoma) for 3 dogs, mild mixed-cell inflammation for 1 dog, and hamartoma for 1 dog. No complications were reported. These findings resulted in a change in treatment recommendations for 3 dogs and confirmed that no additional treatment was required for 1 dog (with hamartoma). For the remaining dog, in which CT findings and clinical history were strongly suggestive of neoplasia, the final diagnosis was rhinitis. Biopsy specimens were safely collected from masses within the nasal and sinus passages of dogs by use of a frameless CTSBS, allowing a definitive diagnosis that was unachievable with other biopsy approaches.

Magnetic Resonance (MR)-Guided Breast Biopsy

MedlinePlus

... the type of biopsy being performed or the design of the biopsy machine, a biopsy of tissue ... cost information. The costs for specific medical imaging tests, treatments and procedures may vary by geographic region. ...

Flange joint system for SRF cavities utilizing high force spring clamps for low particle generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

A flange joint system for SRF cavities. The flange joint system includes a set of high force spring clamps that produce high force on the simple flanges of Superconducting Radio Frequency (SRF) cavities to squeeze conventional metallic seals. The system establishes the required vacuum and RF-tight seal with minimum particle contamination to the inside of the cavity assembly. The spring clamps are designed to stay within their elastic range while being forced open enough to mount over the flange pair. Upon release, the clamps have enough force to plastically deform metallic seal surfaces and continue to a new equilibrium sprungmore » dimension where the flanges remain held against one another with enough preload such that normal handling will not break the seal.« less

Endoscopic ultrasound-guided fine-needle aspiration with on-site cytopathology versus core biopsy: a comparison of both techniques performed at the same endoscopic session

PubMed Central

Lin, Michael; Hair, Clark D.; Green, Linda K.; Vela, Stacie A.; Patel, Kalpesh K.; Qureshi, Waqar A.; Shaib, Yasser H.

2014-01-01

Background: Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) with bedside cytopathology is the gold standard for assessment of pancreatic, subepithelial, and other lesions in close proximity to the gastrointestinal tract, but it is time-consuming, has certain diagnostic limitations, and bedside cytopathology is not widely available. Aims: The goal of this study is to compare the diagnostic yield of EUS-guided FNA with on-site cytopathology and EUS-guided core biopsy. Methods: Twenty-six patients with gastrointestinal mass lesions requiring biopsy at a tertiary medical center were included in this retrospective analysis of a prospective cohort. Two core biopsies were taken using a 22 gauge needle followed by FNA guided by a bedside cytopathologist at the same endoscopic session. The diagnostic yield and test characteristics of EUS core biopsy and EUS FNA with bedside cytopathology were examined. Results: The mean number of passes was 3.2 for FNA, and the mean procedure time was 39.4 minutes. The final diagnosis was malignant in 92.3 %. Sensitivity and specificity were 83 % and 100 %, respectively, for FNA, and 91.7 % and 100 %, respectively, for core biopsy. Diagnostic accuracy was 92.3 % for FNA and 84.6 % for core biopsy. The two approaches were in agreement in 88.4 % with a kappa statistic of 0.66 (95 % confidence interval 0.33 – 0.99). Conclusions: An approach using two passes with a core biopsy needle is comparable to the current gold standard of FNA with bedside cytopathology. The performance of two core biopsies is time-efficient and could represent a good alternative to FNA with bedside cytopathology. PMID:26135096

21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2013 CFR

2013-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...

21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2012 CFR

2012-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...

21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2014 CFR

2014-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...

21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2010 CFR

2010-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...

21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2011 CFR

2011-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...

Number of Biopsies in Diagnosing Pulmonary Nodules

PubMed Central

Wehrschuetz, M.; Wehrschuetz, E.; Portugaller, H. R.

2010-01-01

Purpose: To determine the number of specimens to be obtained from pulmonary lesions to get the highest possible accuracy in histological work-up. Materials and methods: A retrospective evaluation (January 1999 to April 2004) covered 260 patients with thoracic lesions who underwent computer tomography (CT)-guided core-cut biopsy in coaxial technique. All biopsies were performed utilizing a 19 gauge introducer needle and a 20 gauge core-cut biopsy needle. In all, 669 usable biopsies were taken (from 1–5 biopsies in each setting). The specimens were marked sequentially and each biopsy was worked up histologicaly. The biopsy results were correlated to histology after surgery, clinical follow-up or autopsy. The number of biopsies was determined that is necessary to achieve the highest possible accuracy in diagnosing pulmonary lesions. Results: In 591 of 669 biopsies (88.3%), there were correct positive results. The overall accuracy was 87.4%. In 193 of 260 (74.2%) patients, a suspected malignancy was confirmed. In 50 of 260 (19.2%) patients, a benign lesion was correctly diagnosed. Seventeen (6.5%) patients were lost to follow-up. The first, second and third biopsies had cumulative accuracies of 63.6%, 89.2% and 91.5%, respectively (P < 0.02). More biopsies did not show any higher impact on accuracy. Conclusion: For the highest possible accuracy in diagnosing pulmonary lesions by CT-guided core-cut biopsy, at least three usable specimens are recommended to be taken. PMID:21157523

Optimizing EUS-guided liver biopsy sampling: comprehensive assessment of needle types and tissue acquisition techniques.

PubMed

Schulman, Allison R; Thompson, Christopher C; Odze, Robert; Chan, Walter W; Ryou, Marvin

2017-02-01

EUS-guided liver biopsy sampling using FNA and, more recently, fine-needle biopsy (FNB) needles has been reported with discrepant diagnostic accuracy, in part due to differences in methodology. We aimed to compare liver histologic yields of 4 EUS-based needles and 2 percutaneous needles to identify optimal number of needle passes and suction. Six needle types were tested on human cadaveric tissue: one 19G FNA needle, one existing 19G FNB needle, one novel 19G FNB needle, one 22G FNB needle, and two 18G percutaneous needles (18G1 and 18G2). Two needle excursion patterns (1 vs 3 fanning passes) were performed on all EUS needles. Primary outcome was number of portal tracts. Secondary outcomes were degree of fragmentation and specimen adequacy. Pairwise comparisons were performed using t tests, with a 2-sided P < .05 considered to be significant. Multivariable regression analysis was performed. In total, 288 liver biopsy samplings (48 per needle type) were performed. The novel 19G FNB needle had significantly increased mean portal tracts compared with all needle types. The 22G FNB needle had significantly increased portal tracts compared with the 18G1 needle (3.8 vs 2.5, P < .001) and was not statistically different from the 18G2 needle (3.8 vs 3.5, P = .68). FNB needles (P < .001) and 3 fanning passes (P ≤ .001) were independent predictors of the number of portal tracts. A novel 19G EUS-guided liver biopsy needle provides superior histologic yield compared with 18G percutaneous needles and existing 19G FNA and core needles. Moreover, the 22G FNB needle may be adequate for liver biopsy sampling. Investigations are underway to determine whether these results can be replicated in a clinical setting. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Optimization of prostate biopsy: the role of magnetic resonance imaging targeted biopsy in detection, localization and risk assessment.

PubMed

Bjurlin, Marc A; Meng, Xiaosong; Le Nobin, Julien; Wysock, James S; Lepor, Herbert; Rosenkrantz, Andrew B; Taneja, Samir S

2014-09-01

Optimization of prostate biopsy requires addressing the shortcomings of standard systematic transrectal ultrasound guided biopsy, including false-negative rates, incorrect risk stratification, detection of clinically insignificant disease and the need for repeat biopsy. Magnetic resonance imaging is an evolving noninvasive imaging modality that increases the accurate localization of prostate cancer at the time of biopsy, and thereby enhances clinical risk assessment and improves the ability to appropriately counsel patients regarding therapy. In this review we 1) summarize the various sequences that comprise a prostate multiparametric magnetic resonance imaging examination along with its performance characteristics in cancer detection, localization and reporting standards; 2) evaluate potential applications of magnetic resonance imaging targeting in prostate biopsy among men with no previous biopsy, a negative previous biopsy and those with low stage cancer; and 3) describe the techniques of magnetic resonance imaging targeted biopsy and comparative study outcomes. A bibliographic search covering the period up to October 2013 was conducted using MEDLINE®/PubMed®. Articles were reviewed and categorized based on which of the 3 objectives of this review was addressed. Data were extracted, analyzed and summarized. Multiparametric magnetic resonance imaging consists of anatomical T2-weighted imaging coupled with at least 2 functional imaging techniques. It has demonstrated improved prostate cancer detection sensitivity up to 80% in the peripheral zone and 81% in the transition zone. A prostate cancer magnetic resonance imaging suspicion score has been developed, and is depicted using the Likert or PI-RADS (Prostate Imaging Reporting and Data System) scale for better standardization of magnetic resonance imaging interpretation and reporting. Among men with no previous biopsy, magnetic resonance imaging increases the frequency of significant cancer detection to 50

Cost-benefit analysis of biopsy methods for suspicious mammographic lesions; discussion 994-5.

PubMed

Fahy, B N; Bold, R J; Schneider, P D; Khatri, V; Goodnight, J E

2001-09-01

Stereotactic core biopsy (SCB) is more cost-effective than needle-localized biopsy (NLB) for evaluation and treatment of mammographic lesions. A computer-generated mathematical model was developed based on clinical outcome modeling to estimate costs accrued during evaluation and treatment of suspicious mammographic lesions. Total costs were determined for evaluation and subsequent treatment of cancer when either SCB or NLB was used as the initial biopsy method. Cost was estimated by the cumulative work relative value units accrued. The risk of malignancy based on the Breast Imaging Reporting Data System (BIRADS) score and mammographic suspicion of ductal carcinoma in situ were varied to simulate common clinical scenarios. Total cost accumulated during evaluation and subsequent surgical therapy (if required). Evaluation of BIRADS 5 lesions (highly suggestive, risk of malignancy = 90%) resulted in equivalent relative value units for both techniques (SCB, 15.54; NLB, 15.47). Evaluation of lesions highly suspicious for ductal carcinoma in situ yielded similar total treatment relative value units (SCB, 11.49; NLB, 10.17). Only for evaluation of BIRADS 4 lesions (suspicious abnormality, risk of malignancy = 34%) was SCB more cost-effective than NLB (SCB, 7.65 vs. NLB, 15.66). No difference in cost-benefit was found when lesions highly suggestive of malignancy (BIRADS 5) or those suspicious for ductal carcinoma in situ were evaluated initially with SCB vs. NLB, thereby disproving the hypothesis. Only for intermediate-risk lesions (BIRADS 4) did initial evaluation with SCB yield a greater cost savings than with NLB.

Relationship Between Prebiopsy Multiparametric Magnetic Resonance Imaging (MRI), Biopsy Indication, and MRI-ultrasound Fusion-targeted Prostate Biopsy Outcomes.

PubMed

Meng, Xiaosong; Rosenkrantz, Andrew B; Mendhiratta, Neil; Fenstermaker, Michael; Huang, Richard; Wysock, James S; Bjurlin, Marc A; Marshall, Susan; Deng, Fang-Ming; Zhou, Ming; Melamed, Jonathan; Huang, William C; Lepor, Herbert; Taneja, Samir S

2016-03-01

Increasing evidence supports the use of magnetic resonance imaging (MRI)-ultrasound fusion-targeted prostate biopsy (MRF-TB) to improve the detection of clinically significant prostate cancer (PCa) while limiting detection of indolent disease compared to systematic 12-core biopsy (SB). To compare MRF-TB and SB results and investigate the relationship between biopsy outcomes and prebiopsy MRI. Retrospective analysis of a prospectively acquired cohort of men presenting for prostate biopsy over a 26-mo period. A total of 601 of 803 consecutively eligible men were included. All men were offered prebiopsy MRI and assigned a maximum MRI suspicion score (mSS). Men with an MRI abnormality underwent combined MRF-TB and SB. Detection rates for all PCa and high-grade PCa (Gleason score [GS] ≥7) were compared using the McNemar test. MRF-TB detected fewer GS 6 PCas (75 vs 121; p<0.001) and more GS ≥7 PCas (158 vs 117; p<0.001) than SB. Higher mSS was associated with higher detection of GS ≥7 PCa (p<0.001) but was not correlated with detection of GS 6 PCa. Prediction of GS ≥7 disease by mSS varied according to biopsy history. Compared to SB, MRF-TB identified more GS ≥7 PCas in men with no prior biopsy (88 vs 72; p=0.012), in men with a prior negative biopsy (28 vs 16; p=0.010), and in men with a prior cancer diagnosis (42 vs 29; p=0.043). MRF-TB detected fewer GS 6 PCas in men with no prior biopsy (32 vs 60; p<0.001) and men with prior cancer (30 vs 46; p=0.034). Limitations include the retrospective design and the potential for selection bias given a referral population. MRF-TB detects more high-grade PCas than SB while limiting detection of GS 6 PCa in men presenting for prostate biopsy. These findings suggest that prebiopsy multiparametric MRI and MRF-TB should be considered for all men undergoing prostate biopsy. In addition, mSS in conjunction with biopsy indications may ultimately help in identifying men at low risk of high-grade cancer for whom prostate biopsy

Prospective randomized trial comparing magnetic resonance imaging (MRI)-guided in-bore biopsy to MRI-ultrasound fusion and transrectal ultrasound-guided prostate biopsy in patients with prior negative biopsies.

PubMed

Arsov, Christian; Rabenalt, Robert; Blondin, Dirk; Quentin, Michael; Hiester, Andreas; Godehardt, Erhard; Gabbert, Helmut E; Becker, Nikolaus; Antoch, Gerald; Albers, Peter; Schimmöller, Lars

2015-10-01

A significant proportion of prostate cancers (PCas) are missed by conventional transrectal ultrasound-guided biopsy (TRUS-GB). It remains unclear whether the combined approach using targeted magnetic resonance imaging (MRI)-ultrasound fusion-guided biopsy (FUS-GB) and systematic TRUS-GB is superior to targeted MRI-guided in-bore biopsy (IB-GB) for PCa detection. To compare PCa detection between IB-GB alone and FUS-GB + TRUS-GB in patients with at least one negative TRUS-GB and prostate-specific antigen ≥4 ng/ml. Patients were prospectively randomized after multiparametric prostate MRI to IB-GB (arm A) or FUS-GB + TRUS-GB (arm B) from November 2011 to July 2014. The study was powered at 80% to demonstrate an overall PCa detection rate of ≥60% in arm B compared to 40% in arm A. Secondary endpoints were the distribution of highest Gleason scores, the rate of detection of significant PCa (Gleason ≥7), the number of biopsy cores to detect one (significant) PCa, the positivity rate for biopsy cores, and tumor involvement per biopsy core. The study was halted after interim analysis because the primary endpoint was not met. The trial enrolled 267 patients, of whom 210 were analyzed (106 randomized to arm A and 104 to arm B). PCa detection was 37% in arm A and 39% in arm B (95% confidence interval for difference, -16% to 11%; p=0.7). Detection rates for significant PCa (29% vs 32%; p=0.7) and the highest percentage tumor involvement per biopsy core (48% vs 42%; p=0.4) were similar between the arms. The mean number of cores was 5.6 versus 17 (p<0.001). A limitation is the limited number of patients because of early cessation of accrual. This trial failed to identify an important improvement in detection rate for the combined biopsy approach over MRI-targeted biopsy alone. A prospective comparison between MRI-targeted biopsy alone and systematic TRUS-GB is justified. Our randomized study showed similar prostate cancer detection rates between targeted prostate biopsy

NIMBY, CLAMP, and the location of new nuclear-related facilities: U.S. national and 11 site-specific surveys.

PubMed

Greenberg, Michael R

2009-09-01

Public and political opposition have made finding locations for new nuclear power plants, waste management, and nuclear research and development facilities a challenge for the U.S. government and the nuclear industry. U.S. government-owned properties that already have nuclear-related activities and commercial nuclear power generating stations are logical locations. Several studies and utility applications to the Nuclear Regulatory Commission suggest that concentrating locations at major plants (CLAMP) has become an implicit siting policy. We surveyed 2,101 people who lived within 50 miles of 11 existing major nuclear sites and 600 who lived elsewhere in the United States. Thirty-four percent favored CLAMP for new nuclear power plants, 52% for waste management facilities, and 50% for new nuclear laboratories. College educated, relatively affluent male whites were the strongest CLAMP supporters. They disproportionately trusted those responsible for the facilities and were not worried about existing nuclear facilities or other local environmental issues. Notably, they were concerned about continuing coal use. Not surprisingly, CLAMP proponents tended to be familiar with their existing local nuclear site. In short, likely CLAMP sites have a large and politically powerful core group to support a CLAMP policy. The challenge to proponents of nuclear technologies will be to sustain this support and expand the base among those who clearly are less connected and receptive to new nearby sites.

Emission control apparatus for internal combustion engines with a controllably disabled clamping circuit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Asano, M.

1979-08-28

The invention discloses an emission control apparatus for internal combustion engine includes an exhaust composition sensor to sense the mixture ratio, a circuit for clamping the mixture ratio to a predetermined constant value to prevent the mixture from becoming too rich or too lean when a failure should occur in the control loop, for example, in the exhaust composition sensor failure and a circuit for interrupting the clamping circuit when the engine operating condition is such that the sensor is caused to produce low voltage signals although the sensor is functioning properly.

Population patch clamp electrophysiology: a breakthrough technology for ion channel screening.

PubMed

Dale, Tim J; Townsend, Claire; Hollands, Emma C; Trezise, Derek J

2007-10-01

Population patch clamp (PPC) is a novel high throughput planar array electrophysiology technique that allows ionic currents to be recorded from populations of cells under voltage clamp. For the drug discovery pharmacologist, PPC promises greater speed and precision than existing methods for screening compounds at voltage-gated ion channel targets. Moreover, certain constitutively active or slow-ligand gated channels that have hitherto proved challenging to screen with planar array electrophysiology (e.g. SK/IK channels) are now more accessible. In this article we review early findings using PPC and provide a perspective on its likely impact on ion channel drug discovery. To support this, we include some new data on ion channel assay duplexing and on modulator assays, approaches that have thus far not been described.

Breast Biopsy System

NASA Technical Reports Server (NTRS)

1994-01-01

Charge Coupled Devices (CCDs) are high technology silicon chips that connect light directly into electronic or digital images, which can be manipulated or enhanced by computers. When Goddard Space Flight Center (GSFC) scientists realized that existing CCD technology could not meet scientific requirements for the Hubble Space Telescope Imagining Spectrograph, GSFC contracted with Scientific Imaging Technologies, Inc. (SITe) to develop an advanced CCD. SITe then applied many of the NASA-driven enhancements to the manufacture of CCDs for digital mammography. The resulting device images breast tissue more clearly and efficiently. The LORAD Stereo Guide Breast Biopsy system incorporates SITe's CCD as part of a digital camera system that is replacing surgical biopsy in many cases. Known as stereotactic needle biopsy, it is performed under local anesthesia with a needle and saves women time, pain, scarring, radiation exposure and money.

Timing of clamping and factors associated with iron stores in full-term newborns

PubMed Central

Oliveira, Fabiana de Cássia Carvalho; Assis, Karine Franklin; Martins, Mariana Campos; do Prado, Mara Rúbia Maciel Cardoso; Ribeiro, Andréia Queiroz; Sant’Ana, Luciana Ferreira da Rocha; Priore, Silvia Eloiza; Franceschini, Sylvia do Carmo Castro

2014-01-01

OBJECTIVE To analyze the impact of timing of clamping and obstetric, biological and socioeconomic factors on the iron stores of full-term newborns. METHODS Cross-sectional study between October 2011 and July 2012 in which hematological parameters were evaluated for newborns in Viçosa, MG, Southeastern Brazil. It involved collecting 7 mL of umbilical cord blood from 144 full-term not underweight newborns. The parameters investigated were complete blood count, serum iron, ferritin and C-reactive protein. The time of umbilical cord clamping was measured using a digital timer without interfering in the procedures of childbirth. The birth data were collected from Live Birth Certificates and other information was obtained from the mother through a questionnaire applied in the first month postpartum. Analysis of multiple linear regression was then used to estimate the influence of biological, obstetrics and socioeconomic factors on the ferritin levels at birth. RESULTS The median ferritin was 130.3 µg/L (n = 129, minimum = 16.4; maximum = 420.5 µg/L), the mean serum iron was 137.9 μg/dL (n = 144, SD = 39.29) and mean hemoglobin was 14.7 g/dL (n = 144, SD = 1.47). The median time of cord clamping was 36 seconds, ranging between 7 and 100. The bivariate analysis detected an association between ferritin levels and color of the child, timing clamping of 60 seconds, type of delivery, the presence of gestational diabetes and per capita family income. In multivariate analysis, the variables per capita income, number of antenatal visits and length at birth accounted for 22.0% of variation in ferritin levels. CONCLUSIONS Iron stores at birth were influenced by biological, obstetric and social characteristics. Tackling anemia should involve creating policies aimed at reducing social inequalities, improving the quality of antenatal care, as well as implementing a criterion of delayed clamping of the umbilical cord within the guidelines of labor. PMID:24789632

Image guided biopsy of the pleura: a useful diagnostic tool even when fluid is minimal.

PubMed

Manu, Mohan K; Prakashini, Koteshwara; Mohapatra, Aswini Kumar; Kudva, Ranjini

2014-06-30

A man in his late thirties presented with left-sided chest pain, recurrent fever and cough. Radiographical study revealed left pleural effusion which on ultrasonic imaging was minimal and non-tappable. Image guided trucut pleural biopsy yielded pleural specimens which helped in confirming the diagnosis of tuberculosis. 2014 BMJ Publishing Group Ltd.

Target location after deep cerebral biopsies using low-volume air injection in 75 patients. Results and technical note.

PubMed

Poca, Maria A; Martínez-Ricarte, Francisco-Ramon; Gándara, Dario F; Coscojuela, Pilar; Martínez-Sáez, Elena; Sahuquillo, Juan

2017-10-01

Stereotactic biopsy is a minimally invasive technique that allows brain tissue samples to be obtained with low risk. Classically, different techniques have been used to identify the biopsy site after surgery. To describe a technique to identify the precise location of the target in the postoperative CT scan using the injection of a low volume of air into the biopsy cannula. Seventy-five biopsies were performed in 65 adults and 10 children (40 males and 35 females, median age 51 years). Frame-based biopsy was performed in 46 patients, while frameless biopsy was performed in the remaining 29 patients. In both systems, after brain specimens had been collected and with the biopsy needle tip in the center of the target, a small volume of air (median 0.7 cm 3 ) was injected into the site. A follow-up CT scan was performed in all patients. Intracranial air in the selected target was present in 69 patients (92%). No air was observed in two patients (air volume administered in these 2 cases was below 0.7 cm 3 ), while in the remaining four patients blood content was observed in the target. The diagnostic yield in this series was 97.3%. No complications were found to be associated with intracranial air injection in any of the 75 patients who underwent this procedure. The air-injection maneuver proposed for use in stereotactic biopsies of intracranial mass lesions is a safe and reliable technique that allows the exact biopsy site to be located without any related complications.

Histological Value of Duodenal Biopsies

PubMed Central

Gupta, Limci; B., Hamid

2005-01-01

This study was performed to see the value of histopathological diagnosis in management of patients with duodenal biopsies; to look for correlation of histology and serology in suspected cases of coeliac disease; the reasons for taking duodenal biopsies and whether proper adequate histories are provided on the forms sent with request for histopathological view on duodenal biopsies. Here are the observations of the study followed by the discussion. PMID:15915293

Novel 384-well population patch clamp electrophysiology assays for Ca2+-activated K+ channels.

PubMed

John, Victoria H; Dale, Tim J; Hollands, Emma C; Chen, Mao Xiang; Partington, Leanne; Downie, David L; Meadows, Helen J; Trezise, Derek J

2007-02-01

Planar array electrophysiology techniques were applied to assays for modulators of recombinant hIK and hSK3 Ca2+-activated K+ channels. In CHO-hIK-expressing cells, under asymmetric K+ gradients, small-molecule channel activators evoked time- and voltage-independent currents characteristic of those previously described by classical patch clamp electrophysiology methods. In single-hole (cell) experiments, the large cell-to-cell heterogeneity in channel expression rendered it difficult to generate activator concentration-response curves. However, in population patch clamp mode, in which signals are averaged from up to 64 cells, well-to-well variation was substantially reduced such that concentration-response curves could be easily constructed. The absolute EC50 values and rank order of potency for a range of activators, including 1-EBIO and DC-EBIO, corresponded well with conventional patch clamp data. Activator responses of hIK and hSK3 channels could be fully and specifically blocked by the selective inhibitors TRAM-34 and apamin, with IC50 values of 0.31 microM and 3 nM, respectively. To demonstrate assay precision and robustness, a test set of 704 compounds was screened in a 384-well format of the hIK assay. All plates had Z' values greater than 0.6, and the statistical cutoff for activity was 8%. Eleven hits (1.6%) were identified from this set, in addition to the randomly spiked wells with known activators. Overall, our findings demonstrate that population patch clamp is a powerful and enabling method for screening Ca2+-activated K+ channels and provides significant advantages over single-cell electrophysiology (IonWorks(HT)) and other previously published approaches. Moreover, this work demonstrates for the 1st time the utility of population patch clamp for ion channel activator assays and for non-voltage-gated ion channels.

Subclinical rejection associated with chronic allograft nephropathy in protocol biopsies as a risk factor for late graft loss.

PubMed

Moreso, F; Ibernon, M; Gomà, M; Carrera, M; Fulladosa, X; Hueso, M; Gil-Vernet, S; Cruzado, J M; Torras, J; Grinyó, J M; Serón, D

2006-04-01

Chronic allograft nephropathy (CAN) in protocol biopsies is associated with graft loss while the association between subclinical rejection (SCR) and outcome has yielded contradictory results. We analyze the predictive value of SCR and/or CAN in protocol biopsies on death-censored graft survival. Since 1988, a protocol biopsy was done during the first 6 months in stable grafts with serum creatinine <300 micromol/L and proteinuria <1 g/day. Biopsies were evaluated according to Banff criteria. Borderline changes and acute rejection were grouped as SCR. CAN was defined as presence of interstitial fibrosis and tubular atrophy. Mean follow-up was 91 +/- 46 months. Sufficient tissue was obtained in 435 transplants. Biopsies were classified as normal (n = 186), SCR (n = 74), CAN (n = 110) and SCR with CAN (n = 65). Presence of SCR with CAN was associated with old donors, percentage of panel reactive antibodies and presence of acute rejection before protocol biopsy. Cox regression analysis showed that SCR with CAN (relative risk [RR]: 1.86, 95% confidence interval [CI]: 1.11-3.12; p = 0.02) and hepatitis C virus (RR: 2.27, 95% CI: 1.38-3.75; p = 0.01) were independent predictors of graft survival. In protocol biopsies, the detrimental effect of interstitial fibrosis/tubular atrophy on long-term graft survival is modulated by SCR.

Basics of kidney biopsy: A nephrologist's perspective

PubMed Central

Agarwal, S. K.; Sethi, S.; Dinda, A. K.

2013-01-01

The introduction of the kidney biopsy is one of the major events in the history of nephrology. Primary indications of kidney biopsy are glomerular hematuria/proteinuria with or without renal dysfunction and unexplained renal failure. Kidney biopsy is usually performed in prone position but in certain situations, supine and lateral positions may be required. Biopsy needles have changed with times from Vim–Silverman needle to Tru-cut needle to spring-loaded automatic gun. The procedure has also changed from blind bedside kidney biopsy to ultrasound marking to real-time ultrasound guidance to rarely computerized tomography guidance and laparoscopic and open biopsy. In very specific situations, transjugular kidney biopsy may be required. Most of the centers do kidney biopsy on short 1-day admission, whereas some take it as an outdoor procedure. For critical interpretation of kidney biopsy, adequate sample and clinical information are mandatory. Tissue needs to be stained with multiple stains for delineation of various components of kidney tissue. Many consider that electron microscopy (EM) is a must for all kidney biopsies, but facilities for EM are limited even in big centers. Sophisticated tests such as immunohistochemistry and in-situ hybridization are useful adjuncts for definitive diagnosis in certain situations. PMID:23960337

Computed Tomography-Guided Biopsy for Potts Disease: An Institutional Experience from an Endemic Developing Country

PubMed Central

Waqas, Muhammad; Qadeer, Mohsin; Faiz, Faizuddin; Alvi, Mohammad Ali

2015-01-01

Study Design A retrospective chart review. Purpose In endemic resource poor countries like Pakistan, most patients are diagnosed and treated for Potts disease on clinical and radiological grounds without a routine biopsy. The purpose of this study was to evaluate the use and effect of computed tomography (CT)-guided biopsy in the management of Potts disease since the technique is becoming increasingly available. Overview of Literature CT-guided biopsy of spinal lesions is routinely performed. Literature on the utility of the technique in endemic resource poor countries is little. Methods This study was conducted at the Neurosurgery section of Aga Khan University Hospital Karachi. All the patients with suspected Potts disease who underwent CT-guided biopsy during the 7 year period from 2007 to 2013 were included in this study. Details of the procedure, histopathology and microbiology were recorded. Results One hundred and seventy-eight patients were treated for suspected Potts disease during the study period. CT-guided biopsies of the spinal lesions were performed in 91 patients (51.12%). Of the 91 procedures, 22 (24.2%) were inconclusive because of inadequate sample (10), normal tissue (6) or reactive tissue (6). Sixty-nine biopsies were positive (75.8%). Granulomatous inflammation was seen in 58 patients (84.05%), positive acid-fast bacillus (AFB) smear in 4 (5.7%) and positive AFB culture in 12 patients (17.3%). All 91 cases in which CT-guided biopsy was performed responded positively to antituberculosis therapy (ATT). Conclusions 75.8% of the specimens yielded positive diagnoses. Granulomatous inflammation on histopathology was the commonest diagnostic feature. In this series, the rates of positive AFB smear and culture were low compared to previous literature. PMID:26097654

Purification of cardiac myocytes from human heart biopsies for gene expression analysis.

PubMed

Kosloski, L M; Bales, I K; Allen, K B; Walker, B L; Borkon, A M; Stuart, R S; Pak, A F; Wacker, M J

2009-09-01

The collection of gene expression data from human heart biopsies is important for understanding the cellular mechanisms of arrhythmias and diseases such as cardiac hypertrophy and heart failure. Many clinical and basic research laboratories conduct gene expression analysis using RNA from whole cardiac biopsies. This allows for the analysis of global changes in gene expression in areas of the heart, while eliminating the need for more complex and technically difficult single-cell isolation procedures (such as flow cytometry, laser capture microdissection, etc.) that require expensive equipment and specialized training. The abundance of fibroblasts and other cell types in whole biopsies, however, can complicate gene expression analysis and the interpretation of results. Therefore, we have designed a technique to quickly and easily purify cardiac myocytes from whole cardiac biopsies for RNA extraction. Human heart tissue samples were collected, and our purification method was compared with the standard nonpurification method. Cell imaging using acridine orange staining of the purified sample demonstrated that >98% of total RNA was contained within identifiable cardiac myocytes. Real-time RT-PCR was performed comparing nonpurified and purified samples for the expression of troponin T (myocyte marker), vimentin (fibroblast marker), and alpha-smooth muscle actin (smooth muscle marker). Troponin T expression was significantly increased, and vimentin and alpha-smooth muscle actin were significantly decreased in the purified sample (n = 8; P < 0.05). Extracted RNA was analyzed during each step of the purification, and no significant degradation occurred. These results demonstrate that this isolation method yields a more purified cardiac myocyte RNA sample suitable for downstream applications, such as real-time RT-PCR, and allows for more accurate gene expression changes in cardiac myocytes from heart biopsies.

An accurate online calibration system based on combined clamp-shape coil for high voltage electronic current transformers.

PubMed

Li, Zhen-hua; Li, Hong-bin; Zhang, Zhi

2013-07-01

Electronic transformers are widely used in power systems because of their wide bandwidth and good transient performance. However, as an emerging technology, the failure rate of electronic transformers is higher than that of traditional transformers. As a result, the calibration period needs to be shortened. Traditional calibration methods require the power of transmission line be cut off, which results in complicated operation and power off loss. This paper proposes an online calibration system which can calibrate electronic current transformers without power off. In this work, the high accuracy standard current transformer and online operation method are the key techniques. Based on the clamp-shape iron-core coil and clamp-shape air-core coil, a combined clamp-shape coil is designed as the standard current transformer. By analyzing the output characteristics of the two coils, the combined clamp-shape coil can achieve verification of the accuracy. So the accuracy of the online calibration system can be guaranteed. Moreover, by employing the earth potential working method and using two insulating rods to connect the combined clamp-shape coil to the high voltage bus, the operation becomes simple and safe. Tests in China National Center for High Voltage Measurement and field experiments show that the proposed system has a high accuracy of up to 0.05 class.

Biopsy

MedlinePlus

... report). The biopsy test is not an exact science. In cases of difficult or unusual problems, second opinions can be helpful. Back to Index The medical information provided in this site is for educational purposes only and is the property of the American ...

Series resistance compensation for whole-cell patch-clamp studies using a membrane state estimator

PubMed Central

Sherman, AJ; Shrier, A; Cooper, E

1999-01-01

Whole-cell patch-clamp techniques are widely used to measure membrane currents from isolated cells. While suitable for a broad range of ionic currents, the series resistance (R(s)) of the recording pipette limits the bandwidth of the whole-cell configuration, making it difficult to measure rapid ionic currents. To increase bandwidth, it is necessary to compensate for R(s). Most methods of R(s) compensation become unstable at high bandwidth, making them hard to use. We describe a novel method of R(s) compensation that overcomes the stability limitations of standard designs. This method uses a state estimator, implemented with analog computation, to compute the membrane potential, V(m), which is then used in a feedback loop to implement a voltage clamp; we refer to this as state estimator R(s) compensation. To demonstrate the utility of this approach, we built an amplifier incorporating state estimator R(s) compensation. In benchtop tests, our amplifier showed significantly higher bandwidths and improved stability when compared with a commercially available amplifier. We demonstrated that state estimator R(s) compensation works well in practice by recording voltage-gated Na(+) currents under voltage-clamp conditions from dissociated neonatal rat sympathetic neurons. We conclude that state estimator R(s) compensation should make it easier to measure large rapid ionic currents with whole-cell patch-clamp techniques. PMID:10545359

CT Scan-Guided Abrams' Needle Pleural Biopsy versus Ultrasound-Assisted Cutting Needle Pleural Biopsy for Diagnosis in Patients with Pleural Effusion: A Randomized, Controlled Trial.

PubMed

Metintas, Muzaffer; Yildirim, Huseyin; Kaya, Tamer; Ak, Guntulu; Dundar, Emine; Ozkan, Ragip; Metintas, Selma

2016-01-01

Image-guided pleural biopsies, both using ultrasound (US) or computed tomography (CT), are important in the diagnosis of pleural disease. However, no consensus exists regarding which biopsy needles are appropriate for specific procedures. In this randomized, prospective study, we aimed to compare CT scan-guided pleural biopsy using an Abrams' needle (CT-ANPB) with US-assisted pleural biopsy using a cutting needle (US-CNPB) with respect to both diagnostic yield and safety. Between February 2009 and April 2013, 150 patients with exudative pleural effusion who could not be diagnosed by cytological analysis were included in the study. The patients were randomized into either the US-CNPB group or the CT-ANPB group. The two groups were compared in terms of diagnostic sensitivity and complications. Of the 150 patients enrolled in this study, 45 were diagnosed with malignant mesothelioma, 46 were diagnosed with metastatic pleural disease, 18 were diagnosed with pleural tuberculosis, 34 were diagnosed with benign pleural disease, and 7 were lost to follow-up. In the US-CNPB group, the diagnostic sensitivity was 66.7%, compared with 82.4% in the CT-ANPB group; the difference between the two groups was statistically significant (p = 0.029). The sensitivity of CT-ANPB increased to 93.7% for patients with a pleural thickness ≥1 cm. The complication rates were low and acceptable. The first diagnostic intervention that should be preferred in patients with pleural effusion and associated pleural thickening on a CT scan is CT-ANPB. US-CNPB should be used primarily in cases for which only pleural thickening but no pleural effusion is noted. © 2016 S. Karger AG, Basel.

Enhanced Monitoring of Nanosecond Electric Pulse-Evoked Membrane Conductance Changes in Whole-Cell Patch Clamp Experiments.

PubMed

Yoon, Jihwan; Leblanc, Normand; Zaklit, Josette; Vernier, P Thomas; Chatterjee, Indira; Craviso, Gale L

2016-10-01

Patch clamp electrophysiology serves as a powerful method for studying changes in plasma membrane ion conductance induced by externally applied high-intensity nanosecond electric pulses (NEPs). This paper describes an enhanced monitoring technique that minimizes the length of time between pulse exposure and data recording in a patch-clamped excitable cell. Whole-cell membrane currents were continuously recorded up to 11 ms before and resumed 8 ms after delivery of a 5-ns, 6 MV/m pulse by a pair of tungsten rod electrodes to a patched adrenal chromaffin cell maintained at a holding potential of -70 mV. This timing was achieved by two sets of relay switches. One set was used to disconnect the patch pipette electrode from the pre-amplifier and connect it to a battery to maintain membrane potential at -70 mV, and also to disconnect the reference electrode from the amplifier. The other set was used to disconnect the electrodes from the pulse generator until the time of NEP/sham exposure. The sequence and timing of both sets of relays were computer-controlled. Using this procedure, we observed that a 5-ns pulse induced an instantaneous inward current that decayed exponentially over the course of several minutes, that a second pulse induced a similar response, and that the current was carried, at least in part, by Na + . This approach for characterizing ion conductance changes in an excitable cell in response to NEPs will yield information essential for assessing the potential use of NEP stimulation for therapeutic applications.

Lipid-glass adhesion in giga-sealed patch-clamped membranes.

PubMed

Opsahl, L R; Webb, W W

1994-01-01

Adhesion between patch-clamped lipid membranes and glass micropipettes is measured by high contrast video imaging of the mechanical response to the application of suction pressure across the patch. The free patch of membrane reversibly alters both its contact angle and radius of curvature on pressure changes. The assumption that an adhesive force between the membrane and the pipette can sustain normal tension up to a maximum Ta at the edge of the free patch accounts for the observed mechanical responses. When the normal component of the pressure-induced membrane tension exceeds Ta membrane at the contact point between the free patch and the lipid-glass interface is pulled away from the pipette wall, resulting in a decreased radius of curvature for the patch and an increased contact angle. Measurements of the membrane radius of curvature as a function of the suction pressure and pipette radius determine line adhesion tensions Ta which range from 0.5 to 4.0 dyn/cm. Similar behavior of patch-clamped cell membranes implies similar adhesion mechanics.

21 CFR 876.1075 - Gastroenterology-urology biopsy instrument.

Code of Federal Regulations, 2010 CFR

2010-04-01

... generic type of device includes the biopsy punch, gastrointestinal mechanical biopsy instrument, suction... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gastroenterology-urology biopsy instrument. 876... Gastroenterology-urology biopsy instrument. (a) Identification. A gastroenterology-urology biopsy instrument is a...

21 CFR 876.1075 - Gastroenterology-urology biopsy instrument.

Code of Federal Regulations, 2011 CFR

2011-04-01

... generic type of device includes the biopsy punch, gastrointestinal mechanical biopsy instrument, suction... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gastroenterology-urology biopsy instrument. 876... Gastroenterology-urology biopsy instrument. (a) Identification. A gastroenterology-urology biopsy instrument is a...

Conformational analysis of processivity clamps in solution demonstrates that tertiary structure does not correlate with protein dynamics.

PubMed

Fang, Jing; Nevin, Philip; Kairys, Visvaldas; Venclovas, Česlovas; Engen, John R; Beuning, Penny J

2014-04-08

The relationship between protein sequence, structure, and dynamics has been elusive. Here, we report a comprehensive analysis using an in-solution experimental approach to study how the conservation of tertiary structure correlates with protein dynamics. Hydrogen exchange measurements of eight processivity clamp proteins from different species revealed that, despite highly similar three-dimensional structures, clamp proteins display a wide range of dynamic behavior. Differences were apparent both for structurally similar domains within proteins and for corresponding domains of different proteins. Several of the clamps contained regions that underwent local unfolding with different half-lives. We also observed a conserved pattern of alternating dynamics of the α helices lining the inner pore of the clamps as well as a correlation between dynamics and the number of salt bridges in these α helices. Our observations reveal that tertiary structure and dynamics are not directly correlated and that primary structure plays an important role in dynamics. Copyright © 2014 Elsevier Ltd. All rights reserved.

A novel measuring method of clamping force for electrostatic chuck in semiconductor devices

NASA Astrophysics Data System (ADS)

Kesheng, Wang; Jia, Cheng; Yin, Zhong; Linhong, Ji

2016-04-01

Electrostatic chucks are one of the core components of semiconductor devices. As a key index of electrostatic chucks, the clamping force must be controlled within a reasonable range. Therefore, it is essential to accurately measure the clamping force. To reduce the negative factors influencing measurement precision and repeatability, this article presents a novel method to measure the clamping force and we elaborate both the principle and the key procedure. A micro-force probe component is introduced to monitor, adjust, and eliminate the gap between the wafer and the electrostatic chuck. The contact force between the ruby probe and the wafer is selected as an important parameter to characterize de-chucking, and we have found that the moment of de-chucking can be exactly judged. Moreover, this article derives the formula calibrating equivalent action area of backside gas pressure under real working conditions, which can effectively connect the backside gas pressure at the moment of de-chucking and the clamping force. The experiments were then performed on a self-designed measuring platform. The de-chucking mechanism is discussed in light of our analysis of the experimental data. Determination criteria for de-chucking point are summed up. It is found that the relationship between de-chucking pressure and applied voltage conforms well to quadratic equation. Meanwhile, the result reveals that actual de-chucking behavior is much more complicated than the description given in the classical empirical formula. Project supported by No. 02 National Science and Technology Major Project of China (No. 2011ZX02403-004).

Diagnostic Yield of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

PubMed Central

2011-01-01

Background: New transbronchial needle aspiration (TBNA) technologies have been developed, but their clinical effectiveness and determinants of diagnostic yield have not been quantified. Prospective data are needed to determine risk-adjusted diagnostic yield. Methods: We prospectively enrolled patients undergoing TBNA of mediastinal lymph nodes in the American College of Chest Physicians Quality Improvement Registry, Evaluation, and Education (AQuIRE) multicenter database and recorded clinical, procedural, and provider information. All clinical decisions, including type of TBNA used (conventional vs endobronchial ultrasound-guided), were made by the attending bronchoscopist. The primary outcome was obtaining a specific diagnosis. Results: We enrolled 891 patients at six hospitals. Most procedures (95%) were performed with ultrasound guidance. A specific diagnosis was made in 447 cases. Unadjusted diagnostic yields were 37% to 54% for different hospitals, with significant between-hospital heterogeneity (P = .0001). Diagnostic yield was associated with annual hospital TBNA volume (OR, 1.003; 95% CI, 1.000-1.006; P = .037), smoking (OR, 1.55; 95% CI, 1.02-2.34; P = .042), biopsy of more than two sites (OR, 0.57; 95% CI, 0.38-0.85; P = .015), lymph node size (reference > 1-2 cm, ≤ 1 cm: OR, 0.51; 95% CI, 0.34-0.77; P = .003; > 2-3 cm: OR, 2.49; 95% CI, 1.61-3.85; P < .001; and > 3 cm: OR, 3.61; 95% CI, 2.17-6.00; P < .001), and positive PET scan (OR, 3.12; 95% CI, 1.39-7.01; P = .018). Biopsy was performed on more and smaller nodes at high-volume hospitals (P < .0001). Conclusions: To our knowledge, this is the first bronchoscopy study of risk-adjusted diagnostic yields on a hospital-level basis. High-volume hospitals were associated with high diagnostic yields. This study also demonstrates the value of procedural registries as a quality improvement tool. A larger number and variety of participating hospitals is needed to verify these results and to further

Outcomes of ultrasound guided renal mass biopsies.

PubMed

Sutherland, Edward L; Choromanska, Agnieszka; Al-Katib, Sayf; Coffey, Mary

2018-06-01

The purpose of this study was to evaluate the rate of nondiagnostic ultrasound-guided renal mass biopsies (RMBs) at our institution and to determine what patient, procedural, and focal renal mass (FRM) factors were associated with nondiagnostic ultrasound-guided RMBs. Eighty-two ultrasound-guided renal mass biopsies performed between January 2014 and October 2016 were included in our study. Biopsy outcomes (diagnostic vs. nondiagnostic) and patient, procedural, and FRM characteristics were retrospectively reviewed and recorded. Univariate statistical analyses were performed to identify biopsy characteristics that were indicative of nondiagnostic biopsy. Ultrasound-guided RMBs were diagnostic in 70 out of 82 cases (85%) and non-diagnostic in 12 cases (15%). Among the diagnostic biopsies, 54 (77%) were malignant cases, 94% of which were renal cell carcinoma (RCC). Of the 12 nondiagnostic cases, the final diagnosis was RCC in 4 cases and angiomyolipoma in one case; seven of the nondiagnostic cases were lost to follow-up. A weak association (p = 0.04) was found between the number of needle passes and the biopsy outcome. None of the remaining collected RMB characteristics showed a significant correlation with a diagnostic or nondiagnostic RMB. Six patients (7%) experienced complications. Ultrasound-guided renal mass biopsy is a safe and effective method for the diagnosis of renal masses with a low rate of nondiagnostic outcomes. A nondiagnostic biopsy should not be treated as a surrogate for a diagnosis since a significant number of patients with nondiagnostic biopsies have subsequently been shown to have renal malignancies. Repeat biopsy should be considered in such cases.

21 CFR 876.1075 - Gastroenterology-urology biopsy instrument.

Code of Federal Regulations, 2013 CFR

2013-04-01

... biopsy instrument, gastro-urology biopsy needle and needle set, and nonelectric biopsy forceps. This... regulations. (b) Classification. (1) Class II (performance standards). (2) Class I for the biopsy forceps cover and the non-electric biopsy forceps. The devices subject to this paragraph (b)(2) are exempt from...

21 CFR 876.1075 - Gastroenterology-urology biopsy instrument.

Code of Federal Regulations, 2014 CFR

2014-04-01

... biopsy instrument, gastro-urology biopsy needle and needle set, and nonelectric biopsy forceps. This... regulations. (b) Classification. (1) Class II (performance standards). (2) Class I for the biopsy forceps cover and the non-electric biopsy forceps. The devices subject to this paragraph (b)(2) are exempt from...

21 CFR 876.1075 - Gastroenterology-urology biopsy instrument.

Code of Federal Regulations, 2012 CFR

2012-04-01

... biopsy instrument, gastro-urology biopsy needle and needle set, and nonelectric biopsy forceps. This... regulations. (b) Classification. (1) Class II (performance standards). (2) Class I for the biopsy forceps cover and the non-electric biopsy forceps. The devices subject to this paragraph (b)(2) are exempt from...

Outside-out "sniffer-patch" clamp technique for in situ measures of neurotransmitter release.

PubMed

Muller-Chrétien, Emilie

2014-01-01

The mechanism underlying neurotransmitter release is a critical research domain for the understanding of neuronal network function; however, few techniques are available for the direct detection and measurement of neurotransmitter release. To date, the sniffer-patch clamp technique is mainly used to investigate these mechanisms from individual cultured cells. In this study, we propose to adapt the sniffer-patch clamp technique to in situ detection of neurosecretion. Using outside-out patches from donor cells as specific biosensors plunged in acute cerebral slices, this technique allows for proper detection and quantification of neurotransmitter release at the level of the neuronal network.

A pitfall during endobronchial ultrasound-guided transbronchial forceps biopsy of the mediastinal lymph nodes.

PubMed

Krenke, Rafal; Korczynski, Piotr; Gorska, Katarzyna; Chazan, Ryszarda

2014-03-01

The high diagnostic yield and favorable safety profile of endobronchial ultrasound-guided transbronchial forceps biopsy of the mediastinal lymph nodes have been recently demonstrated. We report an unusual technical problem during endobronchial ultrasound-guided transbronchial forceps biopsy that could be a prerequisite for severe complications. A rupture of the steering band precluded closure of the forceps jaws opened in the subcarinal lymph node. A solution to the problem is presented, together with other procedure-related complications reported in the literature. The report emphasizes that a dysfunction of the forceps steering band can result in severe complications when it occurs during transbronchial sampling of mediastinal lesions. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Scanning electron microscope/energy dispersive x ray analysis of impact residues on LDEF tray clamps

NASA Technical Reports Server (NTRS)

Bernhard, Ronald P.; Durin, Christian; Zolensky, Michael E.

1992-01-01

To better understand the nature of particulates in low-Earth orbit (LEO), and their effects on spacecraft hardware, we are analyzing residues found in impacts on the Long Duration Exposure Facility (LDEF) tray clamps. LDEF experiment trays were held in place by 6 to 8 chromic-anodized aluminum (6061-T6) clamps that were fastened to the spacecraft frame using three stainless steel hex bolts. Each clamp exposed an area of approximately 58 sq cm (4.8 cm x 12.7 cm x .45 cm, minus the bolt coverage). Some 337 out of 774 LDEF tray clamps were archived at JSC and are available through the Meteoroid & Debris Special Investigation Group (M&D SIG). Optical scanning of clamps, starting with Bay/Row A01 and working toward H25, is being conducted at JSC to locate and document impacts as small as 40 microns. These impacts are then inspected by Scanning Electron Microscopy/Energy Dispersive X-ray Analysis (SEM/EDXA) to select those features which contain appreciable impact residue material. Based upon the composition of projectile remnants, and using criteria developed at JSC, we have made a preliminary discrimination between micrometeoroid and space debris residue-containing impact features. Presently, 13 impacts containing significant amounts of unmelted and semi-melted micrometeoritic residues were forwarded to Centre National d'Etudes Spatiales (CNES) in France. At the CNES facilities, the upgraded impacts were analyzed using a JEOL T330A SEM equipped with a NORAN Instruments, Voyager X-ray Analyzer. All residues were quantitatively characterized by composition (including oxygen and carbon) to help understand interplanetary dust as possibly being derived from comets and asteroids.

Flip the tip: an automated, high quality, cost-effective patch clamp screen.

PubMed

Lepple-Wienhues, Albrecht; Ferlinz, Klaus; Seeger, Achim; Schäfer, Arvid

2003-01-01

The race for creating an automated patch clamp has begun. Here, we present a novel technology to produce true gigaseals and whole cell preparations at a high rate. Suspended cells are flushed toward the tip of glass micropipettes. Seal, whole-cell break-in, and pipette/liquid handling are fully automated. Extremely stable seals and access resistance guarantee high recording quality. Data obtained from different cell types sealed inside pipettes show long-term stability, voltage clamp and seal quality, as well as block by compounds in the pM range. A flexible array of independent electrode positions minimizes consumables consumption at maximal throughput. Pulled micropipettes guarantee a proven gigaseal substrate with ultra clean and smooth surface at low cost.

Large-deflection theory for end compression of long rectangular plates rigidly clamped along two edges

NASA Technical Reports Server (NTRS)

Levy, Samuel; Krupen, Philip

1943-01-01

The von Karman equations for flat plates are solved beyond the buckling load up to edge strains equal to eight time the buckling strain, for the extreme case of rigid clamping along the edges parallel to the load. Deflections, bending stresses, and membrane stresses are given as a function of end compressive load. The theoretical values of effective width are compared with the values derived for simple support along the edges parallel to the load. The increases in effective width due to rigid clamping drops from about 20 percent near the buckling strain to about 8 percent at an edge strain equal to eight times the buckling strain. Experimental values of effective width in the elastic range reported in NACA Technical Note No. 684 are between the theoretical curves for the extremes of simple support and rigid clamping.

Biological cell controllable patch-clamp microchip

NASA Astrophysics Data System (ADS)

Penmetsa, Siva; Nagrajan, Krithika; Gong, Zhongcheng; Mills, David; Que, Long

2010-12-01

A patch-clamp (PC) microchip with cell sorting and positioning functions is reported, which can avoid drawbacks of random cell selection or positioning for a PC microchip. The cell sorting and positioning are enabled by air bubble (AB) actuators. AB actuators are pneumatic actuators, in which air pressure is generated by microheaters within sealed microchambers. The sorting, positioning, and capturing of 3T3 cells by this type of microchip have been demonstrated. Using human breast cancer cells MDA-MB-231 as the model, experiments have been demonstrated by this microchip as a label-free technical platform for real-time monitoring of the cell viability.

Relationship between histopathological changes in post partum renal biopsies and renal function tests of African women with early onset pre-eclampsia.

PubMed

Khedun, S M; Naicker, T; Moodley, J

2000-05-01

To improve the diagnostic accuracy of concurrent renal disease in hypertension of pregnancy, biopsy evaluation is essential. In addition, establishing underlying renal disease is important for prognosis on future pregnancies. We therefore designed a study to determine the diagnostic yield of postpartum renal biopsy and the nature and frequency of complications associated with this procedure. Also, to determine relationships, if any, between renal function tests and ultrastructural and histopathological findings. Fifty renal biopsies were performed in the immediate postpartum period in black African women with early onset pre-eclampsia. Each biopsy specimen was placed in a separate container and coded so that sampling was unknown to the electron microscopist. Each biopsy specimen was divided into three parts, and processed and stained for light, fluorescent and transmission electron microscopy using conventional techniques. Renal tissue biopsies were adequate for diagnostic purposes in all cases. There were no complications in any of the 50 patients studied. Ultrastructural examination confirmed the light microscopy findings. In addition the ultrastructural findings showed intramembranous deposits, foot process fusion and mesangial deposits. In 16 patients with normal renal function tests; the biopsies evaluation from these patients showed ultrastructural changes. In the remaining 34 patients with abnormal renal function tests of varying severity; biopsy evaluation from these patients showed both ultrastructural and histopathological changes. Renal biopsy procedure is safe, and ultrastructural and histological findings obtained from postpartum renal biopsies are more informative than the routine renal function tests.

Rectal forceps biopsy procedure in cystic fibrosis: technical aspects and patients perspective for clinical trials feasibility

PubMed Central

2013-01-01

Background Measurements of CFTR function in rectal biopsies ex vivo have been used for diagnosis and prognosis of Cystic Fibrosis (CF) disease. Here, we aimed to evaluate this procedure regarding: i) viability of the rectal specimens obtained by biopsy forceps for ex vivo bioelectrical and biochemical laboratory analyses; and ii) overall assessment (comfort, invasiveness, pain, sedation requirement, etc.) of the rectal forceps biopsy procedure from the patients perspective to assess its feasibility as an outcome measure in clinical trials. Methods We compared three bowel preparation solutions (NaCl 0.9%, glycerol 12%, mannitol), and two biopsy forceps (standard and jumbo) in 580 rectal specimens from 132 individuals (CF and non-CF). Assessment of the overall rectal biopsy procedure (obtained by biopsy forceps) by patients was carried out by telephone surveys to 75 individuals who underwent the sigmoidoscopy procedure. Results Integrity and friability of the tissue specimens correlate with their transepithelial resistance (r = −0.438 and −0.305, respectively) and are influenced by the bowel preparation solution and biopsy forceps used, being NaCl and jumbo forceps the most compatible methods with the electrophysiological analysis. The great majority of the individuals (76%) did not report major discomfort due to the short procedure time (max 15 min) and considered it relatively painless (79%). Importantly, most (88%) accept repeating it at least for one more time and 53% for more than 4 times. Conclusions Obtaining rectal biopsies with a flexible endoscope and jumbo forceps after bowel preparation with NaCl solution is a safe procedure that can be adopted for both adults and children of any age, yielding viable specimens for CFTR bioelectrical/biochemical analyses. The procedure is well tolerated by patients, demonstrating its feasibility as an outcome measure in clinical trials. PMID:23688510

Rectal forceps biopsy procedure in cystic fibrosis: technical aspects and patients perspective for clinical trials feasibility.

PubMed

Servidoni, Maria F; Sousa, Marisa; Vinagre, Adriana M; Cardoso, Silvia R; Ribeiro, Maria A; Meirelles, Luciana R; de Carvalho, Rita B; Kunzelmann, Karl; Ribeiro, Antônio F; Ribeiro, José D; Amaral, Margarida D

2013-05-20

Measurements of CFTR function in rectal biopsies ex vivo have been used for diagnosis and prognosis of Cystic Fibrosis (CF) disease. Here, we aimed to evaluate this procedure regarding: i) viability of the rectal specimens obtained by biopsy forceps for ex vivo bioelectrical and biochemical laboratory analyses; and ii) overall assessment (comfort, invasiveness, pain, sedation requirement, etc.) of the rectal forceps biopsy procedure from the patients perspective to assess its feasibility as an outcome measure in clinical trials. We compared three bowel preparation solutions (NaCl 0.9%, glycerol 12%, mannitol), and two biopsy forceps (standard and jumbo) in 580 rectal specimens from 132 individuals (CF and non-CF). Assessment of the overall rectal biopsy procedure (obtained by biopsy forceps) by patients was carried out by telephone surveys to 75 individuals who underwent the sigmoidoscopy procedure. Integrity and friability of the tissue specimens correlate with their transepithelial resistance (r = -0.438 and -0.305, respectively) and are influenced by the bowel preparation solution and biopsy forceps used, being NaCl and jumbo forceps the most compatible methods with the electrophysiological analysis. The great majority of the individuals (76%) did not report major discomfort due to the short procedure time (max 15 min) and considered it relatively painless (79%). Importantly, most (88%) accept repeating it at least for one more time and 53% for more than 4 times. Obtaining rectal biopsies with a flexible endoscope and jumbo forceps after bowel preparation with NaCl solution is a safe procedure that can be adopted for both adults and children of any age, yielding viable specimens for CFTR bioelectrical/biochemical analyses. The procedure is well tolerated by patients, demonstrating its feasibility as an outcome measure in clinical trials.

Sequencing of intraductal biopsies is feasible and potentially impacts clinical management of patients with indeterminate biliary stricture and cholangiocarcinoma.

PubMed

Bankov, Katrin; Döring, Claudia; Schneider, Markus; Hartmann, Sylvia; Winkelmann, Ria; Albert, Joerg G; Bechstein, Wolf Otto; Zeuzem, Stefan; Hansmann, Martin Leo; Peveling-Oberhag, Jan; Walter, Dirk

2018-04-30

Definite diagnosis and therapeutic management of cholangiocarcinoma (CCA) remains a challenge. The aim of the current study was to investigate feasibility and potential impact on clinical management of targeted sequencing of intraductal biopsies. Intraductal biopsies with suspicious findings from 16 patients with CCA in later clinical course were analyzed with targeted sequencing including tumor and control benign tissue (n = 55 samples). A CCA-specific sequencing panel containing 41 genes was designed and a dual strand targeted enrichment was applied. Sequencing was successfully performed for all samples. In total, 79 mutations were identified and a mean of 1.7 mutations per tumor sample (range 0-4) as well as 2.3 per biopsy (0-6) were detected and potentially therapeutically relevant genes were identified in 6/16 cases. In 14/18 (78%) biopsies with dysplasia or inconclusive findings at least one mutation was detected. The majority of mutations were found in both surgical specimen and biopsy (68%), while 28% were only present in biopsies in contrast to 4% being only present in the surgical tumor specimen. Targeted sequencing from intraductal biopsies is feasible and potentially improves the diagnostic yield. A profound genetic heterogeneity in biliary dysplasia needs to be considered in clinical management and warrants further investigation. The current study is the first to demonstrate the feasibility of sequencing of intraductal biopsies which holds the potential to impact diagnostic and therapeutical management of patients with biliary dysplasia and neoplasia.

Analysis of failed and nickel-coated 3093 beam clamp components at the East Tennessee Technology Park (ETTP).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, D.; Pappacena, K.; Gaviria, J.

2010-10-11

The U.S. Department of Energy and its contractor, Bechtel Jacobs Company (BJC), are undertaking a major effort to clean up the former gaseous diffusion facility (K-25) located in Oak Ridge, TN. The decontamination and decommissioning activities require systematic removal of contaminated equipment and machinery followed by demolition of the buildings. As part of the cleanup activities, a beam clamp, used for horizontal life lines (HLLs) for fall protection, was discovered to be fractured during routine inspection. The beam clamp (yoke and D-ring) was a component in the HLL system purchased from Reliance Industries LLC. Specifically, the U-shaped stainless steel yokemore » of the beam clamp failed in a brittle mode at under less than 10% of the rated design capacity of 14,500 lb. The beam clamp had been in service for approximately 16 months. Bechtel Jacobs approached Argonne National Laboratory to assist in identifying the root cause of the failure of the beam clamp. The objectives of this study were to (1) review the prior reports and documents on the subject, (2) understand the possible failure mechanism(s) that resulted in the failed beam clamp components, (3) recommend approaches to mitigate the failure mechanism(s), and (4) evaluate the modified beam clamp assemblies. Energy dispersive x-ray analysis and chemical analysis of the corrosion products on the failed yoke and white residue on an in-service yoke indicated the presence of zinc, sulfur, and calcium. Analysis of rainwater in the complex, as conducted by BJC, indicated the presence of sulfur and calcium. It was concluded that, as a result of galvanic corrosion, zinc from the galvanized components of the beam clamp assembly (D-ring) migrated to the corroded region in the presence of the rainwater. Under mechanical stress, the corrosion process would have accelerated, resulting in the catastrophic failure of the yoke. As suggested by Bechtel Jacobs personnel, hydrogen embrittlement as a consequence of

MRI-Targeted or Standard Biopsy for Prostate-Cancer Diagnosis.

PubMed

Kasivisvanathan, Veeru; Rannikko, Antti S; Borghi, Marcelo; Panebianco, Valeria; Mynderse, Lance A; Vaarala, Markku H; Briganti, Alberto; Budäus, Lars; Hellawell, Giles; Hindley, Richard G; Roobol, Monique J; Eggener, Scott; Ghei, Maneesh; Villers, Arnauld; Bladou, Franck; Villeirs, Geert M; Virdi, Jaspal; Boxler, Silvan; Robert, Grégoire; Singh, Paras B; Venderink, Wulphert; Hadaschik, Boris A; Ruffion, Alain; Hu, Jim C; Margolis, Daniel; Crouzet, Sébastien; Klotz, Laurence; Taneja, Samir S; Pinto, Peter; Gill, Inderbir; Allen, Clare; Giganti, Francesco; Freeman, Alex; Morris, Stephen; Punwani, Shonit; Williams, Norman R; Brew-Graves, Chris; Deeks, Jonathan; Takwoingi, Yemisi; Emberton, Mark; Moore, Caroline M

2018-05-10

Multiparametric magnetic resonance imaging (MRI), with or without targeted biopsy, is an alternative to standard transrectal ultrasonography-guided biopsy for prostate-cancer detection in men with a raised prostate-specific antigen level who have not undergone biopsy. However, comparative evidence is limited. In a multicenter, randomized, noninferiority trial, we assigned men with a clinical suspicion of prostate cancer who had not undergone biopsy previously to undergo MRI, with or without targeted biopsy, or standard transrectal ultrasonography-guided biopsy. Men in the MRI-targeted biopsy group underwent a targeted biopsy (without standard biopsy cores) if the MRI was suggestive of prostate cancer; men whose MRI results were not suggestive of prostate cancer were not offered biopsy. Standard biopsy was a 10-to-12-core, transrectal ultrasonography-guided biopsy. The primary outcome was the proportion of men who received a diagnosis of clinically significant cancer. Secondary outcomes included the proportion of men who received a diagnosis of clinically insignificant cancer. A total of 500 men underwent randomization. In the MRI-targeted biopsy group, 71 of 252 men (28%) had MRI results that were not suggestive of prostate cancer, so they did not undergo biopsy. Clinically significant cancer was detected in 95 men (38%) in the MRI-targeted biopsy group, as compared with 64 of 248 (26%) in the standard-biopsy group (adjusted difference, 12 percentage points; 95% confidence interval [CI], 4 to 20; P=0.005). MRI, with or without targeted biopsy, was noninferior to standard biopsy, and the 95% confidence interval indicated the superiority of this strategy over standard biopsy. Fewer men in the MRI-targeted biopsy group than in the standard-biopsy group received a diagnosis of clinically insignificant cancer (adjusted difference, -13 percentage points; 95% CI, -19 to -7; P<0.001). The use of risk assessment with MRI before biopsy and MRI-targeted biopsy was superior to

An accurate online calibration system based on combined clamp-shape coil for high voltage electronic current transformers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhen-hua; Li, Hong-bin; Zhang, Zhi

Electronic transformers are widely used in power systems because of their wide bandwidth and good transient performance. However, as an emerging technology, the failure rate of electronic transformers is higher than that of traditional transformers. As a result, the calibration period needs to be shortened. Traditional calibration methods require the power of transmission line be cut off, which results in complicated operation and power off loss. This paper proposes an online calibration system which can calibrate electronic current transformers without power off. In this work, the high accuracy standard current transformer and online operation method are the key techniques. Basedmore » on the clamp-shape iron-core coil and clamp-shape air-core coil, a combined clamp-shape coil is designed as the standard current transformer. By analyzing the output characteristics of the two coils, the combined clamp-shape coil can achieve verification of the accuracy. So the accuracy of the online calibration system can be guaranteed. Moreover, by employing the earth potential working method and using two insulating rods to connect the combined clamp-shape coil to the high voltage bus, the operation becomes simple and safe. Tests in China National Center for High Voltage Measurement and field experiments show that the proposed system has a high accuracy of up to 0.05 class.« less

Sonographically guided percutaneous muscle biopsy in diagnosis of neuromuscular disease: a useful alternative to open surgical biopsy.

PubMed

O'Sullivan, Paul J; Gorman, Grainne M; Hardiman, Orla M; Farrell, Michael J; Logan, P Mark

2006-01-01

The purpose of this study was to evaluate the feasibility of sonographically guided percutaneous muscle biopsy in the investigation of neuromuscular disorders. Sonographically guided percutaneous needle biopsy of skeletal muscle was performed with a 14-gauge core biopsy system in 40 patients over a 24-month period. Patients were referred from the Department of Neurology under investigation for neuromuscular disorders. Sonography was used to find suitable tissue and to avoid major vascular structures. A local anesthetic was applied below skin only. A 3- to 4-mm incision was made. Three 14-gauge samples were obtained from each patient. All samples were placed on saline-dampened gauze and sent for neuropathologic analysis. As a control, we retrospectively assessed results of the 40 most recent muscle samples acquired via open surgical biopsy. With the use of sonography, 32 (80%) of 40 patients had a histologic diagnosis made via percutaneous needle biopsy. This included 26 (93%) of 28 patients with acute muscular disease and 6 (50%) of 12 patients with chronic disease. In the surgical group (all acute disease), 38 (95%) of 40 patients had diagnostic tissue attained. Sonographically guided percutaneous 14-gauge core skeletal muscle biopsy is a useful procedure, facilitating diagnosis in acute muscular disease. It provides results comparable with those of open surgical biopsy in acute muscular disease. It may also be used in chronic muscular disease but repeated or open biopsy may be needed.

Jumbo forceps are superior to standard large-capacity forceps in obtaining diagnostically adequate inflammatory bowel disease surveillance biopsy specimens.

PubMed

Elmunzer, B Joseph; Higgins, Peter D R; Kwon, Yong M; Golembeski, Christopher; Greenson, Joel K; Korsnes, Sheryl J; Elta, Grace H

2008-08-01

In inflammatory bowel disease (IBD) surveillance colonoscopy, an increased number of biopsy specimens correlates with a higher dysplasia detection rate. Larger biopsy specimens may also increase the diagnostic yield. To compare a new jumbo forceps with a standard large-capacity forceps in obtaining diagnostically adequate IBD surveillance biopsy specimens. Prospective single-center study. Twenty-four patients who were undergoing an IBD surveillance colonoscopy were enrolled. As part of standard IBD surveillance, 8 paired biopsy specimens were obtained from the rectosigmoid by using the jumbo forceps and a standard large-capacity forceps. Biopsy specimens were deemed adequate if they met all 3 of the following criteria: (1) length > or =3 mm, (2) penetration into the muscularis mucosa, and (3) < 20% crush artifact. The proportion of adequate biopsy specimens obtained with the jumbo forceps was significantly higher than that obtained with the large-capacity control forceps (67% vs 48%, P < .0001). The average length of the biopsy specimen obtained with the jumbo forceps was 4.00 mm (95% CI, 3.81-4.20 mm) compared with 3.19 mm (95% CI, 2.99-3.38 mm) with the large-capacity (control) forceps. (1) No validated outcome measurement for the quality of GI biopsy specimens exists and (2) in this study, interobserver variability between pathologists was high. The jumbo forceps was superior to a standard large-capacity forceps in obtaining diagnostically adequate IBD surveillance biopsy specimens. Because biopsy specimens obtained with the jumbo forceps were larger, the use of this forceps for IBD surveillance will allow the endoscopist to sample a larger colonic mucosal surface area, potentially resulting in an increased dysplasia detection rate.

Are concurrent systematic cores needed at the time of targeted biopsy in patients with prior negative prostate biopsies?

PubMed

Albisinni, S; Aoun, F; Noel, A; El Rassy, E; Lemort, M; Paesmans, M; van Velthoven, R; Roumeguère, T; Peltier, A

2018-01-01

MRI-guided targeted biopsies are advised in patients who have undergone an initial series of negative systematic biopsies, in whom prostate cancer (PCa) suspicion remains elevated. The aim of the study was to evaluate whether, in men with prior negative prostate biopsies, systematic cores are also warranted at the time of an MRI-targeted repeat biopsy. We enrolled patients with prior negative biopsy undergoing real time MRI/TRUS fusion guided prostate biopsy at our institute between 2014 and 2016. Patients with at least one index lesion on multiparametric MRI were included. All eligible patients underwent both systematic random biopsies (12-14 cores) and targeted biopsies (2-4 cores). The study included 74 men with a median age of 65 years, PSA level of 9.27ng/mL, and prostatic volume of 45ml. The overall PCa detection rate and the clinically significant cancer detection rate were 56.7% and 39.2%, respectively. Targeted cores demonstrated similar clinically significant PCa detection rate compared to systematic cores (33.8% vs. 28.4%, P=0.38) with significantly less tissue sampling. Indeed, a combination approach was significantly superior to a targeted-only in overall PCa detection (+16.7% overall detection rate, P=0.007). Although differences in clinically significant PCa detection were statistically non-significant (P=0.13), a combination approach did allow detecting 7 extra clinically significant PCas (+13.8%). In patients with elevated PSA and prior negative biopsies, concurrent systematic sampling may be needed at the time of targeted biopsy in order to maximize PCa detection rate. Larger studies are needed to validate our findings. 4. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Comparison of the complications of traditional 12 cores transrectal prostate biopsy with image fusion guided transperineal prostate biopsy.

PubMed

Huang, Haifeng; Wang, Wei; Lin, Tingsheng; Zhang, Qing; Zhao, Xiaozhi; Lian, Huibo; Guo, Hongqian

2016-11-17

To compare the complications of traditional transrectal (TR) prostate biopsy and image fusion guided transperineal (TP) prostate biopsy in our center. Two hundred and fourty-two patients who underwent prostate biopsy from August 2014 to January 2015were reviewed. Among them, 144 patients underwent systematic 12-core transrectal ultrasonography (TRUS) guided prostate biopsy (TR approach) while 98 patients underwent free-hand transperineal targeted biopsy with TRUS and multi-parameter magnetic resonance imaging (mpMRI) fusion images (TP approach). The complications of the two groups were presented and a simple statistical analysis was performed to compare the two groups. The cohort of our study include242 patients, including 144 patients underwent TR biopsies while 98 patients underwentTP biopsies. There was no significant difference of major complications, including sepsis, bleeding and other complication requiring admissionbetween the two groups (P > 0.05). The incidence rate of infection and rectal bleeding in TR was much higher than TP (p < 0.05), but the incidence rate of perineal swelling in TP was much higher than TR (p < 0.05). There were no significant differences of minor complications including hematuria, lower urinary tract symptoms (LUTS), dysuria, and acuteurinary retention between the two groups (p > 0.05). The present study supports the safety of both techniques. Free-handTP targeted prostate biopsy with real-time fusion imaging of mpMRI and TR ultrasound is a good approach for prostate biopsy.

Biopsy

MedlinePlus

... portion of the lump is removed surgically. This type of biopsy is most commonly used for tumors of the skin to distinguish benign conditions and diagnose cancers and other tumors. This can be done by 'shave', 'curette' or 'punch' methods. A " shave " slices a surface portion off with ...

Comparison of detection limit in fiber-based conventional, amplified, and gain-clamped cavity ring-down techniques

NASA Astrophysics Data System (ADS)

Sharma, K.; Abdul Khudus, M. I. M.; Alam, S. U.; Bhattacharya, S.; Venkitesh, D.; Brambilla, G.

2018-01-01

Relative performance and detection limit of conventional, amplified, and gain-clamped cavity ring-down techniques (CRDT) in all-fiber configurations are compared experimentally for the first time. Refractive index measurement using evanescent field in tapered fibers is used as a benchmark for the comparison. The systematic optimization of a nested-loop configuration in gain-clamped CRDT is also discussed, which is crucial for achieving a constant gain in a CRDT experiment. It is found that even though conventional CRDT has the lowest standard error in ring-down time (Δτ), the value of ring-down time (τ) is very small, thus leading to poor detection limit. Amplified CRDT provides an improvement in τ, albeit with two orders of magnitude higher Δτ due to amplifier noise. The nested-loop configuration in gain-clamped CRDT helps in reducing Δτ by an order of magnitude as compared to amplified CRDT whilst retaining the improvement in τ. A detection limit of 1 . 03 × 10-4 RIU at refractive index of 1.322 with a 3 mm long and 4.5 μm diameter tapered fiber is demonstrated with the gain-clamped CRDT.

Plugged percutaneous biopsy of the liver in living-donor liver transplantation recipients suspected to have graft rejection.

PubMed

Kim, Sung Jung; Won, Je Hwan; Kim, Young Bae; Wang, Hee-Jung; Kim, Bong-Wan; Kim, Haeryoung; Kim, Jinoo

2017-07-01

Background Percutaneous biopsy is a widely-accepted technique for acquiring histologic samples of the liver. When there is concern for bleeding, plugged percutaneous biopsy (PPB) may be performed, which involves embolization of the biopsy tract. Purpose To evaluate the efficacy and safety of PPB of the liver in patients suspected to have graft rejection after living-donor liver transplantation (LDLT). Material and Methods During January 2007 and December 2013, 51 patients who underwent PPB of the liver under the suspicion of post-LDLT graft rejection were retrospectively analyzed. A total of 73 biopsies were performed. Biopsy was performed with a 17-gauge core needle and 18-gauge cutting needle. The needle tract was embolized using gelatin sponge (n = 44) or N-butyl cyanoacrylate (NBCA) (n = 29). The specimens were reviewed to determine their adequacy for histologic diagnosis. We reviewed all medical records after PPB. Results Specimens were successfully acquired in all procedures (100%). They were adequate for diagnosis in 70 cases (95.9%) and inadequate in three (1.3%). Average of 9.8 complete portal tracts was counted per specimen. One minor complication (1.4%) occurred where the patient had transient fever after the procedure. Conclusion PPB is easy and safe to perform in LDLT recipients and provides high diagnostic yield.

Accurate measurement of junctional conductance between electrically coupled cells with dual whole-cell voltage-clamp under conditions of high series resistance.

PubMed

Hartveit, Espen; Veruki, Margaret Lin

2010-03-15

Accurate measurement of the junctional conductance (G(j)) between electrically coupled cells can provide important information about the functional properties of coupling. With the development of tight-seal, whole-cell recording, it became possible to use dual, single-electrode voltage-clamp recording from pairs of small cells to measure G(j). Experiments that require reduced perturbation of the intracellular environment can be performed with high-resistance pipettes or the perforated-patch technique, but an accompanying increase in series resistance (R(s)) compromises voltage-clamp control and reduces the accuracy of G(j) measurements. Here, we present a detailed analysis of methodologies available for accurate determination of steady-state G(j) and related parameters under conditions of high R(s), using continuous or discontinuous single-electrode voltage-clamp (CSEVC or DSEVC) amplifiers to quantify the parameters of different equivalent electrical circuit model cells. Both types of amplifiers can provide accurate measurements of G(j), with errors less than 5% for a wide range of R(s) and G(j) values. However, CSEVC amplifiers need to be combined with R(s)-compensation or mathematical correction for the effects of nonzero R(s) and finite membrane resistance (R(m)). R(s)-compensation is difficult for higher values of R(s) and leads to instability that can damage the recorded cells. Mathematical correction for R(s) and R(m) yields highly accurate results, but depends on accurate estimates of R(s) throughout an experiment. DSEVC amplifiers display very accurate measurements over a larger range of R(s) values than CSEVC amplifiers and have the advantage that knowledge of R(s) is unnecessary, suggesting that they are preferable for long-duration experiments and/or recordings with high R(s). Copyright (c) 2009 Elsevier B.V. All rights reserved.

The hypertriglyceridemic clamp technique. Studies using long-chain and structured triglyceride emulsions in healthy subjects.

PubMed

Nordenström, Jörgen; Thörne, Anders; Aberg, Wiveca; Carneheim, Claes; Olivecrona, Thomas

2006-11-01

In a randomized crossover study, plasma kinetics of 2 different types of fat emulsions were studied in 8 healthy volunteers by using a hypertriglyceridemic clamp technique. The method involves the stabilization of serum triglyceride (TG) concentration during 180 minutes at a predetermined level (4 mmol/L) by adjustment of TG infusion rate by repeated online measurements of serum TG concentration. The fat emulsions under study were a long-chain fatty acid triglyceride (LCT) emulsion (Intralipid 20%, Fresenius Kabi, Sweden) and a structured triglyceride (STG) emulsion (Structolipid 20%, Fresenius Kabi) where medium- and long-chain fatty acids have been interesterified within a TG molecule. The hypertriglyceridemic clamp was found to have acceptable reproducibility when tested in 3 healthy individuals on 2 different occasions, as similar steady-state TG levels were obtained by infusing similar amounts of fat. The average (+/-SEM) TG concentration during the 180-minute clamp was similar for STGs and LCTs (4.0 +/- 0.1 vs 3.9 +/- 0.1 mmol/L; not significant), but the amount of fat that had to be infused was significantly higher during STG than during LCT clamping (0.31 +/- 0.04 vs 0.21 +/- 0.02 g TG per minute; P < .05). Higher serum levels of free fatty acids (1.80 +/- 0.13 vs 0.96 +/- 0.09 mmol/L; P < .05), free glycerol (1.30 +/- 0.07 vs 0.76 +/- 0.08 mmol/L; P < .001), and beta-OH butyrate (1.61 +/- 0.44 vs 1.17 +/- 0.23 mmol/L; not significant) were obtained at the end of the clamp during infusion of STGs compared with LCTs. During infusion of STGs the medium-chain fatty acids octanoic (C:8) and decanoic acid (C:10) constituted approximately half of circulating fatty acids that correspond to the compositional ratio of the emulsion. Plasma lipoprotein lipase (LPL) concentration was higher during STG than during LCT clamping (6.06 +/- 0.62 vs 3.15 +/- 0.40 mU/mL; P < .05), and there was a positive correlation between the mean LPL concentration and the amount of

Rectal transection using a curved cutter stapler with an endo-Satinsky clamp during a laparoscopic low anterior resection.

PubMed

Hotta, Tsukasa; Takifuji, Katsunari; Yokoyama, Shozo; Matsuda, Kenji; Yamaue, Hiroki

2012-10-01

A new rectal transaction method was developed using a combination of the curved cutter stapler and endo-Satinsky clamp because of the difficulty in performing rectal transection in the narrow pelvic cavity. The endo-Satinsky clamp is inserted without a flexible trocar cannula by connecting the handle extra-abdominally with a shaft of the endo-Satinsky clamp through the left higher quadrant port via a retrograde course from a midline incision above the pubis symphysis. The endo-Satinsky clamp is used to clamp the rectal wall horizontally at the distal end of the tumor. The wrist of an elastic surgical glove fixed with the shaft of the curved cutter stapler is covered with a midline incision, and consequently, the stapler is inserted into the pelvic cavity. The curved head of the stapler is rotated to the left at the anal side of the endo-Satinsky clamp to insert the rectum between the jaws of the stapler. The stapler is closed and fired, and a rectal transection is thus performed with one firing using a single cartridge. This method was performed in 12 patients with rectal cancer. The median value and range of the tumor distance from the anal verge were 7.0 and 4.5-11.0 cm, respectively. The median duration of the operation was 252 min, and the median blood loss was 15 mL. Only one stapling cartridge was used for rectal transection in all cases, and no major complications were observed. We herein demonstrated a new transection method for rectal cancer.

Sentinel Lymph Node Biopsy in Endometrial Cancer: a New Standard of Care?

PubMed

Sullivan, Stephanie A; Rossi, Emma C

2017-09-18

Lymph node status is one of the most important factors in determining prognosis and the need for adjuvant treatment in endometrial cancer (EMCA). Unfortunately, full lymphadenectomy bears significant surgical and postoperative risks. The majority of patients with clinical stage I disease will not have metastatic disease; thus, a full lymphadenectomy only increases morbidity in this population of patients. The use of the sentinel lymph node (SLN) biopsy has emerged as an alternative to complete lymphadenectomy in EMCA. By removing the highest yield lymph nodes, the SLN biopsy has the same diagnostic ability as lymphadenectomy while minimizing morbidity. The sensitivity of sentinel lymph node identification with robotic fluorescence imaging for detecting metastatic endometrial and cervical cancer (FIRES) trial published this year is the largest prospective, multi-institution trial investigating the accuracy of the SLN biopsy for endometrial and cervical cancer. Results of this trial found an excellent sensitivity (97.2%) and false negative rate (3%) with the technique. The conclusions from the FIRES trial and those of a recent meta-analysis are that SLN biopsy has an acceptable diagnostic accuracy in detecting lymphatic metastases, and can replace lymphadenectomy for this diagnostic purpose. There remains controversy surrounding the SLN biopsy in high-risk disease and the use of adjuvant therapy in the setting of low volume disease detected with ultrastaging. Current data suggests that the technique is accurate in high-risk disease and that the increased detection of metastasis helps guide adjuvant therapy such that oncologic outcomes are likely not affected by forgoing a full lymphadenectomy. Further prospective study is needed to investigate the impact of low volume metastatic disease on oncologic outcomes and the need for adjuvant therapy in these patients.